evolutionnewsandviews--2020-09-19--Kimberella and Controversial Relationships — A Chronological Synopsis, Continued

Editor ’ s note : We are delighted to present a series of posts by paleontologist Günter Bechly on the Ediacaran organism Kimberella .
If identified as an animal , it would “ predate the Cambrian explosion of bilaterian animal phyla as a kind of ‘ advance guard.
’ ” The question is of interest for debates about evolution and arguments about intelligent design raised by Stephen Meyer , among others .
Find the full series about Kimberella here .
In an article about the origins of multicellularity , Knoll ( 2011 ) said that “ Kimberella , shares many @ @ @ @ @ @ @ its preserved characters suggest a stem-group bilaterian.
” He also postulated that “ these animals must have had coordinated muscles capable of sustained locomotion , a digestive system for processing food captured using a radula-like oral apparatus , and a circulatory system that freed Kimberella from diffusional constraints , ” even though none of these characters is preserved in any of the Kimberella fossils ( note : Fedonkin et al .
2007b actually said that “ a true circulatory system may have been absent in Kimberella “ ) .
Nielsen ( 2012 ) @ @ @ @ @ @ @ evolution and the interrelationships of animal phyla .
As in the first edition of his book ( Nielsen 2001 ) , he remained unconvinced by previous attributions of Kimberella and remarked : “ The Late Precambrian Kimberella has been interpreted as a mollusc … , but the reconstruction shows a periphery with a ‘ crenellated zone ’ that does not resemble any known structure from living molluscs , and there is no sign of foot , mouth , or radula .
Long scratches in the microbial mat near the anterior end of some @ @ @ @ @ @ @ … , but the relationships of Kimberella still seem uncertain.
” Ivantsov ( 2010b , 2012 ) listed several characters ( dorsal sclerites , mouth with teeth , foot adapted for crawling ) that he considered to be “ sufficient to assume a molluscan affinity of Kimberella , ” but also listed several conflicting characters ( e.g.
, different feeding apparatus and movement , absence of sensor processes , dorsal muscles ) .
He concluded that “ probably , Kimberella is only closely related to mollusks , but it is not a mollusk @ @ @ @ @ @ @ one of the early evolution stages of trochophore animals , when their extant phyla had not been yet formed.
” He closed his article with the clear statement that the “ available fossils give us no solid evidences of mollusks ’ occurrence in the Precambrian.
” Vendrasco ( 2012 ) criticized previous attributions of Kimberella to the stem of mollusks and said “ their hypothesis lacks strong support , and this is exacerbated by the uncertain placement of Kimberella.
” Therefore , he preferred to classify Kimberella among the Ediacaran “ fossil problematica.
@ @ @ @ @ @ @ considered Kimberella “ to be one of the few Ediacaran body fossils that require placement higher than the Cnidaria ” ( quoted in Budd & Jensen 2017 ) .
Ivantsov ( 2013 ) simply stated that in his opinion “ Kimberella had little to do with mollusks , although it was probably a primitive trochophoran animal ( Trochozoa ) .
” Scherholz et al .
( 2013 ) only briefly mentioned that the attribution of Kimberella to the crown- or stem-group of mollusks is uncertain and presented evidence that simple worm-like aplacophoran mollusks @ @ @ @ @ @ @ This is also supported by the fossil armored aplacophoran Kulindroplax perissokomos described by Sutton et al .
2012 from the Silurian of England .
This finding of course undermines the claim that Kimberella resembles the assumed molluscan ground plan .
Stöger et al .
( 2013 ) said that “ The Vendian ( 555 Ma ) body fossil Kimberella was discussed as a mollusc , but not widely accepted as such , and rather treated as lophotrochozoan stem member or ‘ no more specifically than as a bilaterian.
’ ” However , because @ @ @ @ @ @ @ origin of mollusks in the Precambrian , Stöger et al .
at least considered that “ Kimberella appears late enough in the fossil record to be considered as a potential stem mollusc.
” Furthermore , they maintained that “ Kimberella corresponds to the description of molluscan stem-group features ” because it seems to share the following four characters as putative synapomorphies with molluscs in their cladistic analysis : bipartite radula , foot with gliding sole , circumpedal mantle cavity , separate mantle covered with cuticula .
It is interesting that none of these @ @ @ @ @ @ @ in Kimberella .
It is also noteworthy that their reconstruction of internal mollusk relationships is contradicted by virtually all other recent studies ( Ponder & Lindberg 2008 , Nielsen 2012 , Kocot 2013 , Schrödel & Stöger 2014 , Vinther 2014 , 2015 , Sigwart & Lindberg 2015 , Parkhaev 2017 , Giribet & Edgecombe 2020 , Kocot et al .
2020 ) and thus has to be considered as highly controversial and doubtful .
Anyway , the authors concluded : Gehling et al .
( 2014 ) found that Kimberichnus “ supports @ @ @ @ @ @ @ globally before the Cambrian explosion of life ” and “ point to the systematic feeding excavation of seafloor microbial mats by large bilaterians of molluscan grade.
” However , they also cautioned that “ closer examination of the K. teruzzii arrays provides some contrary evidence ” to a molluscan affinity of the trace-maker .
They emphasized that extant gastropods always move forward in the direction of their radular feeding , but never backward unlike Kimberella .
They concluded that “ Kimberella and its feeding scratches are best explained as evidence of basal crown @ @ @ @ @ @ @ but they considered the affinities of Kimberella to be uncertain .
Grazhdankin ( 2014 ) called Kimberella a “ tissue-grade organism , ” which he attributed to a newly created Ediacaran phylum called Bilateralomorpha , also comprising the potentially related genera Brachina and Solza as well as very different problematic organisms with bilateral body symmetry like for example Parvancorina and Temnoxa .
Schrödl & Stöger ( 2014 ) thought that recent phylogenomic studies , which “ recovered Mollusca as a basal offshoot of a lophotrochozoan ( spiralian ) clade , ” are well @ @ @ @ @ @ @ molecular clock approaches.
” They also speculated that characters like a sinusoidal body cavity and a ciliated foot could be plesiomorphic ground plan characters “ for Kimberella and other molluscs.
” Scheltema ( 2014 ) said that “ besides being a grazer , Kimberella appears to be a stem belonging to the total group Mollusca .
As defined here , it has a stiff , noncalcareous , organic dorsal covering ( but see Ivantsov 2009 ) , a ventral muscular , flat-soled foot , and a space ( mantle cavity ) between dorsum @ @ @ @ @ @ @ basic body plan for Mollusca although with many variations.
” Shu et al .
( 2014 ) referred to Kimberella as “ a possible soft-bodied mollusk , ” but just two pages later as “ possible stem lophotrochozoan.
” Obviously , a lot is possible .
Sperling et al .
( 2015 ) , who studied the Ediacaran-Cambrian oxygenation , said that “ large triploblastic Ediacaran organisms , such as Kimberella ( commonly but not definitively thought to be related to the mollusks ; … ) , moved across the seafloor , making @ @ @ @ @ @ @ , ” and therefore claimed that the “ combination of Kimberella ’ s size , locomotion , and feeding mode would have required both a blood vascular system and much higher minimum oxygen levels.
” Vinther ( 2015 ) concluded that “ Kimberella from the latest Ediacaran exhibits several molluscan traits , which justifies its position as a molluscan stem-group member , rather than as a more basal Lophotrochozoan.
” He emphasized that “ these impressions resemble a molluscan body plan in having a distinct creeping sole ( foot ) and a surrounding @ @ @ @ @ @ @ ” and “ the dorsal surface exhibits a cuticular shield with tubercular nodes.
” His main argument for a mollusk affinity was the association with “ creeping and scraping marks suggestive of a ciliary gliding organism with a molluscan-style radula ” ( Vinther et al .
2012 ) as well as the presence of a paired structure at the tubular end , which he interpreted as resembling esophageal pouches that are only known in mollusks like monoplacophorans , chitons , and gastropods .
However , Vinther acknowledged that “ Kimberella does not offer @ @ @ @ @ @ @ molluscan evolution as it does not possess a biomineralized skeleton.
” Bowyer et al .
( 2017 ) considered Kimberella as a “ bilaterian organism ” and “ probably motile early molluscan organism.
” Budd & Jensen ( 2017 ) , after a careful and thorough review of all the published evidence , were much more prudent .
In spite of all the previous attributions to bilaterian animals , they mentioned that “ there is a curious similarity of some elongate Kimberella to fronds … , the rounded terminal structures would be attachments @ @ @ @ @ @ @ as body fossil parts.
” On the other hand they said that “ general similarities can also be found between Kimberella and Palaeophragmodictya spinosa ( Serezhnikova , 2009 ) , with an outer zone and an inner zone with ‘ hand ’ -like structures that in Kimberella have been interpreted as longitudinal muscle .
The possibility that Kimberella is coelenterate grade should therefore not be excluded ( see also Erwin , 2008 ) .
” They found that “ although likely a metazoan , its placement remains problematic ; it may be on @ @ @ @ @ @ @ the stem group of any particular phylum — this is not incompatible with it retaining some coelenterate-grade features , ” and conclude that “ the affinities of Kimberella remain highly uncertain , but there seems to be no good reason to regard it as a mollusc ; its most likely placement is in the stem-group of the Bilateria.
” Cunningham et al .
( 2017 ) agreed that “ the presence of differentiated anterior-posterior anatomy and bilateral symmetry , comparatively large size , a possible radula-like structure , and evidence of movement suggest @ @ @ @ @ @ @ However , they cautioned that “ suggestions of a more derived affinity place too much credence on the inference of a molluscan radula , and the nature of the mantle-like structure.
” Concerning the feeding traces , they remarked that “ there remain unresolved questions regarding how these scratches were formed and by what kind of structure … , and there is insufficient evidence to test whether the structure that produced them was homologous with a molluscan radula.
” Ivantsov ( 2017 ) said that Kimberella is “ representing the Bilateria ” and @ @ @ @ @ @ @ Trochozoa … and probably , was close to the ancestors of mollusks.
” Parkhaev ( 2017 ) discussed the arguments for a molluscan affinity of Kimberella and considered this assignment as doubtful , mainly because the reconstruction of Kimberella does not conform to the mollusk archetype .
The biggest issue is “ the direction of movement , since all of the mollusks crawl head first .
Secondly , the style of feeding is absolutely untypical for mollusks , because when they ‘ scrape ’ the food substrate by a radula , they make @ @ @ @ @ @ @ Ivanov , 1990 , text-fig .
6 ) , since that radula is located on their tongue within the throat , but not on the anterior appendage of the head .
Therefore , obviously there is no homology between the ‘ teeth ’ of Kimberella and the radula of mollusks.
” He also rejected the dorsal sclerites as evidence for a molluscan nature , because they are only indirectly inferred and are found in various phyla .
He concluded that “ it is difficult to assign Kimberella to any known phylum of metazoans @ @ @ @ @ @ @ of Bilateria , ” and that any ancestors of mollusks can not be detected yet among the soft-bodied organisms of the Vendian biota .
Vinther et al .
( 2017 ) described the Ordovician Calvapilosa kroegeri , which is a siphonogonuchid and very similar to halkieriids .
It definitely proved the presence of a true radula and established the molluscan affinity of halkieriids ( also see Wanninger & Wollesen 2019 ) .
In their phylogenetic analyses ( see extended data figure 8 in their supplementary information ) , which included most early fossils @ @ @ @ @ @ @ the stem group of mollusks .
Darroch et al .
( 2018 ) listed Kimberella in their tree as lophotrochozoan and maintained that “ Kimberella is the best candidate for a bilaterian metazoan , possessing a number of mollusk-like characteristics : Kimberella was likely mobile , preserves evidence for a muscular ‘ foot ’ , and is commonly associated with scratch marks ( Kimberichnus isp . )
, illustrating possession of paired radula-like structures.
” Ivantsov et al .
( 2019 ) considered Kimberella as “ a bilateral symmetric organism close to mollusks.
@ @ @ @ @ @ @ until 2013 , when he still claimed that it “ had little to do with mollusks ” ( see above ) .
It is interesting that this apparent change of mind is not based on any new fossil evidence , but maybe rather on peer pressure .
Wanninger & Wollesen ( 2019 ) discussed the similarities of Kimberella with basal mollusks and placed Kimberella as most basal branch of stem mollusk in their tree of molluscan phylogeny and evolution .
They listed the presence of a single shell and dorso-ventral muscles as only @ @ @ @ @ @ @ are highly doubtful for Kimberella .
Kocot et al .
( 2020 ) presented the most recent phylogenetic analysis of mollusks , as well as a molecular clock study that placed the origin of mollusks in the Precambrian about 584 million years ago .
They commented : Giribet & Edgecombe ( 2020 ) did not take a position in their most up-to-date textbook on the invertebrate tree of life , but merely mentioned that “ the possibility that the Ediacaran fossil Kimberella quadrata … could be a mollusc or a mollusclike bilaterian has @ @ @ @ @ @ @ was first formalized.
” Last but not least , the constantly updated Paleobiology Database lists Kimberella within Metazoa in the unranked clade Kimberellomorpha , thus neither as a bilaterian nor as a stem mollusk .
Next , “ Kimberella Is No Solution to the Cambrian Conundrum .
”

Photo: Kimberella, by the paleobear from Lontananza, Loreto, Peru / CC BY (https://creativecommons.org/licenses/by/2.0).
Editor’s note: We are delighted to present a series of posts by paleontologist Günter Bechly on the Ediacaran organism Kimberella. If identified as an animal, it would “predate the Cambrian explosion of bilaterian animal phyla as a kind of ‘advance guard.’” The question is of interest for debates about evolution and arguments about intelligent design raised by Stephen Meyer, among others. Find the full series about Kimberella here.
In an article about the origins of multicellularity, Knoll (2011) said that “Kimberella, shares many features with mollusks, although in toto its preserved characters suggest a stem-group bilaterian.” He also postulated that “these animals must have had coordinated muscles capable of sustained locomotion, a digestive system for processing food captured using a radula-like oral apparatus, and a circulatory system that freed Kimberella from diffusional constraints,” even though none of these characters is preserved in any of the Kimberella fossils (note: Fedonkin et al. 2007b actually said that “a true circulatory system may have been absent in Kimberella“).
Nielsen (2012) provided an updated standard textbook on animal evolution and the interrelationships of animal phyla. As in the first edition of his book (Nielsen 2001), he remained unconvinced by previous attributions of Kimberella and remarked: “The Late Precambrian Kimberella has been interpreted as a mollusc …, but the reconstruction shows a periphery with a ‘crenellated zone’ that does not resemble any known structure from living molluscs, and there is no sign of foot, mouth, or radula. Long scratches in the microbial mat near the anterior end of some specimens have been interpreted as radular marks …, but the relationships of Kimberella still seem uncertain.”
Ivantsov (2010b, 2012) listed several characters (dorsal sclerites, mouth with teeth, foot adapted for crawling) that he considered to be “sufficient to assume a molluscan affinity of Kimberella,” but also listed several conflicting characters (e.g., different feeding apparatus and movement, absence of sensor processes, dorsal muscles). He concluded that “probably, Kimberella is only closely related to mollusks, but it is not a mollusk itself. It is probably related to one of the early evolution stages of trochophore animals, when their extant phyla had not been yet formed.” He closed his article with the clear statement that the “available fossils give us no solid evidences of mollusks’ occurrence in the Precambrian.”
“Fossil Problematica”
Vendrasco (2012) criticized previous attributions of Kimberella to the stem of mollusks and said “their hypothesis lacks strong support, and this is exacerbated by the uncertain placement of Kimberella.” Therefore, he preferred to classify Kimberella among the Ediacaran “fossil problematica.”
Erwin & Valentine (2013) considered Kimberella “to be one of the few Ediacaran body fossils that require placement higher than the Cnidaria” (quoted in Budd & Jensen 2017).
Ivantsov (2013) simply stated that in his opinion “Kimberella had little to do with mollusks, although it was probably a primitive trochophoran animal (Trochozoa).”
Scherholz et al. (2013) only briefly mentioned that the attribution of Kimberella to the crown- or stem-group of mollusks is uncertain and presented evidence that simple worm-like aplacophoran mollusks evolved from more complex polyplacophoran ancestors. This is also supported by the fossil armored aplacophoran Kulindroplax perissokomos described by Sutton et al. 2012 from the Silurian of England. This finding of course undermines the claim that Kimberella resembles the assumed molluscan ground plan.
Stöger et al. (2013) said that “The Vendian (555 Ma) body fossil Kimberella was discussed as a mollusc, but not widely accepted as such, and rather treated as lophotrochozoan stem member or ‘no more specifically than as a bilaterian.’” However, because all their molecular time trees placed the origin of mollusks in the Precambrian, Stöger et al. at least considered that “Kimberella appears late enough in the fossil record to be considered as a potential stem mollusc.” Furthermore, they maintained that “Kimberella corresponds to the description of molluscan stem-group features” because it seems to share the following four characters as putative synapomorphies with molluscs in their cladistic analysis: bipartite radula, foot with gliding sole, circumpedal mantle cavity, separate mantle covered with cuticula. It is interesting that none of these characters is really unequivocally established as present in Kimberella. It is also noteworthy that their reconstruction of internal mollusk relationships is contradicted by virtually all other recent studies (Ponder & Lindberg 2008, Nielsen 2012, Kocot 2013, Schrödel & Stöger 2014, Vinther 2014, 2015, Sigwart & Lindberg 2015, Parkhaev 2017, Giribet & Edgecombe 2020, Kocot et al. 2020) and thus has to be considered as highly controversial and doubtful. Anyway, the authors concluded:
Our assessment of potential morphological apomorphies and the molecular clock results would suggest that the Vendian (555 Ma) Kimberella is a candidate stem-group mollusc appearing before the evolution of a dorsal shell field. The interpretation of Kimberella is controversial, but the true stem molluscs probably did have a large, bilaterally symmetrical body with subapical mouth on a snout with a likely bipartite radula, a broad ventral foot, many dorsoventral muscle bundles, and a dorsal mantle covered with a resistant dorsal cuticle with mineralised spicules, which are all molluscan features, but lacking a shell.
Uncertain Affinities
Gehling et al. (2014) found that Kimberichnus “supports previous trace fossil evidence that bilaterians existed globally before the Cambrian explosion of life” and “point to the systematic feeding excavation of seafloor microbial mats by large bilaterians of molluscan grade.” However, they also cautioned that “closer examination of the K. teruzzii arrays provides some contrary evidence” to a molluscan affinity of the trace-maker. They emphasized that extant gastropods always move forward in the direction of their radular feeding, but never backward unlike Kimberella. They concluded that “Kimberella and its feeding scratches are best explained as evidence of basal crown group bilaterians with lophotrochozoan affinities,” but they considered the affinities of Kimberella to be uncertain.
Grazhdankin (2014) called Kimberella a “tissue-grade organism,” which he attributed to a newly created Ediacaran phylum called Bilateralomorpha, also comprising the potentially related genera Brachina and Solza as well as very different problematic organisms with bilateral body symmetry like for example Parvancorina and Temnoxa.
Schrödl & Stöger (2014) thought that recent phylogenomic studies, which “recovered Mollusca as a basal offshoot of a lophotrochozoan (spiralian) clade,” are well “consistent with their Precambrian dating in molecular clock approaches.” They also speculated that characters like a sinusoidal body cavity and a ciliated foot could be plesiomorphic ground plan characters “for Kimberella and other molluscs.”
Scheltema (2014) said that “besides being a grazer, Kimberella appears to be a stem belonging to the total group Mollusca. As defined here, it has a stiff, noncalcareous, organic dorsal covering (but see Ivantsov 2009), a ventral muscular, flat-soled foot, and a space (mantle cavity) between dorsum and ventrum containing folded tissue — the basic body plan for Mollusca although with many variations.”
Shu et al. (2014) referred to Kimberella as “a possible soft-bodied mollusk,” but just two pages later as “possible stem lophotrochozoan.” Obviously, a lot is possible.
Sperling et al. (2015), who studied the Ediacaran-Cambrian oxygenation, said that “large triploblastic Ediacaran organisms, such as Kimberella (commonly but not definitively thought to be related to the mollusks; …), moved across the seafloor, making extensive scratch marks on the sediment surface,” and therefore claimed that the “combination of Kimberella’s size, locomotion, and feeding mode would have required both a blood vascular system and much higher minimum oxygen levels.”
Vinther (2015) concluded that “Kimberella from the latest Ediacaran exhibits several molluscan traits, which justifies its position as a molluscan stem-group member, rather than as a more basal Lophotrochozoan.” He emphasized that “these impressions resemble a molluscan body plan in having a distinct creeping sole (foot) and a surrounding mantle separated by a mantle cavity,” and “the dorsal surface exhibits a cuticular shield with tubercular nodes.” His main argument for a mollusk affinity was the association with “creeping and scraping marks suggestive of a ciliary gliding organism with a molluscan-style radula” (Vinther et al. 2012) as well as the presence of a paired structure at the tubular end, which he interpreted as resembling esophageal pouches that are only known in mollusks like monoplacophorans, chitons, and gastropods. However, Vinther acknowledged that “Kimberella does not offer any characters for establishing character polarity in molluscan evolution as it does not possess a biomineralized skeleton.”
Bowyer et al. (2017) considered Kimberella as a “bilaterian organism” and “probably motile early molluscan organism.”
A Careful and Thorough Review
Budd & Jensen (2017), after a careful and thorough review of all the published evidence, were much more prudent. In spite of all the previous attributions to bilaterian animals, they mentioned that “there is a curious similarity of some elongate Kimberella to fronds …, the rounded terminal structures would be attachments and the radiating ridges would be interpreted as body fossil parts.” On the other hand they said that “general similarities can also be found between Kimberella and Palaeophragmodictya spinosa (Serezhnikova, 2009), with an outer zone and an inner zone with ‘hand’-like structures that in Kimberella have been interpreted as longitudinal muscle. The possibility that Kimberella is coelenterate grade should therefore not be excluded (see also Erwin, 2008).” They found that “although likely a metazoan, its placement remains problematic; it may be on the bilaterian stem group rather than within the stem group of any particular phylum — this is not incompatible with it retaining some coelenterate-grade features,” and conclude that “the affinities of Kimberella remain highly uncertain, but there seems to be no good reason to regard it as a mollusc; its most likely placement is in the stem-group of the Bilateria.”
Cunningham et al. (2017) agreed that “the presence of differentiated anterior-posterior anatomy and bilateral symmetry, comparatively large size, a possible radula-like structure, and evidence of movement suggest that Kimberella was a total-group bilaterian.” However, they cautioned that “suggestions of a more derived affinity place too much credence on the inference of a molluscan radula, and the nature of the mantle-like structure.” Concerning the feeding traces, they remarked that “there remain unresolved questions regarding how these scratches were formed and by what kind of structure …, and there is insufficient evidence to test whether the structure that produced them was homologous with a molluscan radula.”
Droser et al. (2017) listed Kimberella as a “putative stem-mollusk.”
Ivantsov (2017) said that Kimberella is “representing the Bilateria” and “probably, could belong to the Trochozoa … and probably, was close to the ancestors of mollusks.”
Parkhaev (2017) discussed the arguments for a molluscan affinity of Kimberella and considered this assignment as doubtful, mainly because the reconstruction of Kimberella does not conform to the mollusk archetype. The biggest issue is “the direction of movement, since all of the mollusks crawl head first. Secondly, the style of feeding is absolutely untypical for mollusks, because when they ‘scrape’ the food substrate by a radula, they make translational movements forward rather than backward (Ivanov, 1990, text-fig. 6), since that radula is located on their tongue within the throat, but not on the anterior appendage of the head. Therefore, obviously there is no homology between the ‘teeth’ of Kimberella and the radula of mollusks.” He also rejected the dorsal sclerites as evidence for a molluscan nature, because they are only indirectly inferred and are found in various phyla. He concluded that “it is difficult to assign Kimberella to any known phylum of metazoans, definitely it is undoubtedly the representative of Bilateria,” and that any ancestors of mollusks cannot be detected yet among the soft-bodied organisms of the Vendian biota.
Vinther et al. (2017) described the Ordovician Calvapilosa kroegeri, which is a siphonogonuchid and very similar to halkieriids. It definitely proved the presence of a true radula and established the molluscan affinity of halkieriids (also see Wanninger & Wollesen 2019). In their phylogenetic analyses (see extended data figure 8 in their supplementary information), which included most early fossils of lophotrochozoans, they resolved Kimberella within the stem group of mollusks.
Darroch et al. (2018) listed Kimberella in their tree as lophotrochozoan and maintained that “Kimberella is the best candidate for a bilaterian metazoan, possessing a number of mollusk-like characteristics: Kimberella was likely mobile, preserves evidence for a muscular ‘foot’, and is commonly associated with scratch marks (Kimberichnus isp.), illustrating possession of paired radula-like structures.”
A Change of Mind
Ivantsov et al. (2019) considered Kimberella as “a bilateral symmetric organism close to mollusks.” This was unlike his earlier papers until 2013, when he still claimed that it “had little to do with mollusks” (see above). It is interesting that this apparent change of mind is not based on any new fossil evidence, but maybe rather on peer pressure.
Wanninger & Wollesen (2019) discussed the similarities of Kimberella with basal mollusks and placed Kimberella as most basal branch of stem mollusk in their tree of molluscan phylogeny and evolution. They listed the presence of a single shell and dorso-ventral muscles as only putative synapomorphies, even though both characters are highly doubtful for Kimberella.
Kocot et al. (2020) presented the most recent phylogenetic analysis of mollusks, as well as a molecular clock study that placed the origin of mollusks in the Precambrian about 584 million years ago. They commented:
The Ediacaran fossil genus Kimberella has been hypothesized to represent a stem-group mollusc by some, but the molluscan affinity of Kimberella has been criticized by others who instead view it as an early-branching bilaterian, in part because of its old age (~555 MYA). Although broad, our and other recent estimates for the divergence of molluscs are at least compatible with hypotheses regarding Kimberella as an early offshoot of the molluscan stemline. However, if Kimberella was indeed a mollusc, it differed from most extant molluscs in its lack of a shell (although sclerites may have been present) and, more significantly, a bizarre rake-like mode of feeding unlike that of any modern mollusc.
Giribet & Edgecombe (2020) did not take a position in their most up-to-date textbook on the invertebrate tree of life, but merely mentioned that “the possibility that the Ediacaran fossil Kimberella quadrata … could be a mollusc or a mollusclike bilaterian has been explored numerous times since that idea was first formalized.”
Last but not least, the constantly updated Paleobiology Database lists Kimberella within Metazoa in the unranked clade Kimberellomorpha, thus neither as a bilaterian nor as a stem mollusk.
Next, “Kimberella Is No Solution to the Cambrian Conundrum.”


evolutionnewsandviews--2020-09-22--Richard Weikart on How Darwinism Fueled Scientific Racism

On a new episode of ID the Future , historian and Cal State Stanislaus emeritus professor Richard Weikart speaks with @ @ @ @ @ dark history of “ scientific ” racism .
Racism , of course , long pre-dated @ @ @ @ @ argues , Darwin and Darwinian evolutionary theory greatly fueled racist thinking in the late 19th @ @ @ @ @ the present .
Download the podcast or listen to it here .
Weikart notes that @ @ @ @ @ racist , ” writing ( in The Descent of Man , 1871 ) that “ @ @ @ @ @ races of man will exterminate and replace throughout the world the savage races.
” Darwin @ @ @ @ @ this ; he thought it would advance human evolution .
His cousin Francis Galton , @ @ @ @ @ , agreed , as did Planned Parenthood founder Margaret Sanger a few years later .

Photo: Visitors admire the iconic Darwin statue at London's Natural History Museum, by Thomas Fabian, via Flickr.
On a new episode of ID the Future, historian and Cal State Stanislaus emeritus professor Richard Weikart speaks with host Michael Keas about the dark history of “scientific” racism. Racism, of course, long pre-dated Darwinism, but as Weikart argues, Darwin and Darwinian evolutionary theory greatly fueled racist thinking in the late 19th century and even down to the present. Download the podcast or listen to it here.
Weikart notes that Darwin himself was “intensely racist,” writing (in The Descent of Man, 1871) that “at some time the civilized races of man will exterminate and replace throughout the world the savage races.” Darwin didn’t merely predict this; he thought it would advance human evolution. His cousin Francis Galton, a strong proponent of eugenics, agreed, as did Planned Parenthood founder Margaret Sanger a few years later.


evolutionnewsandviews--2020-09-22--At What Point In Its Development Can a Human Being Feel Pain?

Editor ’ s note : See also Dr. Wells ’ s earlier article , “ Why Should a Baby Live ?
” This is Part Two of a two-part series about abortion .
This part focuses on the second question I raised in Part One : At what point in its development can a human being feel pain ?
I will attempt to answer the question scientifically , as a developmental biologist .
By “ scientific ” I mean based on evidence , not on materialistic story-telling or the current “ scientific consensus.
” I will conclude with a brief @ @ @ @ @ @ @ first essay was “ Why Should a Baby Live ?
” It was adapted from a 2012 article by Alberto Giubilini and Francesca Minerva , “ After-birth abortion : why should the baby live ?
” That article cites a 1985 book co-authored by Peter Singer titled Should the Baby Live ?
Ten years before , Singer had published his seminal work , Animal Liberation .
In that book he wrote : “ The Darwinian revolution was genuinely revolutionary .
Human beings now knew that they were not the special creation of God @ @ @ @ @ @ @ set apart from the animals ; on the contrary , human beings came to realize that they were animals themselves.
” ( p. 214 ) Singer argued that animals , like humans , deserve protection because of their ability to suffer .
The fact that they can not speak is irrelevant .
We can not refuse “ to attribute pain to those who do not have language… Human infants and young children are unable to use language .
Are we to deny that a year-old child can suffer ?
If not , language @ @ @ @ @ @ @ 15 ) Giubilini and Minerva flipped the logic of the Catholic belief that “ fetuses and newborns share the same moral status ” to argue that because “ abortion is largely accepted , ” newborns ( like fetuses ) do not have a right to life .
But I would flip Peter Singer ’ s logic : If we can not deny that a year-old child can feel pain , how are we to deny that a fetus can feel pain ?
Logic isn ’ t a sufficient answer to the question I @ @ @ @ @ @ @ answer , we need evidence .
At What Point Can a Human Fetus Feel Pain ?
If I gently poke a living cell in a Petri dish , it may recoil from the stimulus .
But people don ’ t usually call that “ pain.
” Dictionary definitions differ , but they generally include ( 1 ) physical and emotional distress due to injury or disease ; ( 2 ) mediation through nerve impulses to the brain ; and ( 3 ) aversive action .
Only the last of these is exhibited by @ @ @ @ @ @ @ If pain requires the transmission of nerve impulses to the brain , then a human embryo ( up to eight weeks post-fertilization ) probably can not feel pain .
( NOTE : I am not arguing that this justifies abortion before eight weeks , only that we can not say that an embryo feels pain in the full sense of the word . )
After eight weeks embryonic age ( ten weeks gestational age ) , a developing human being is called a fetus .
Unfortunately , it is not currently possible to @ @ @ @ @ @ @ can feel pain by working forward from the eight-week stage .
So let ’ s start by working backwards .
From 1964 to 1998 I worked periodically as a clinical laboratory technologist .
One of my responsibilities was to collect blood samples from two-to-three-day-old newborns .
The samples were used to test for phenylketonuria ( PKU ) , an inherited disorder that can occur in as many as 1 out of every 10,000 births .
A baby with PKU can not properly metabolize the amino acid phenylalanine , a necessary nutrient in the @ @ @ @ @ @ @ build-up of toxin that can lead to severe mental impairment , among other things .
If PKU is detected early , however , the child can be fed a special diet that contains only the minimum amount of phenylalanine , and mental impairment can be prevented .
I would routinely collect a drop of blood from a newborn — even if it was premature — by sticking a small , sterile metal blade into its heel .
That blood was used to test for PKU .
Every time I did this , however @ @ @ @ @ @ @ top of his or her tiny lungs , and it would jerk spasmodically in the only aversive activity of which it was capable .
I did it for the baby ’ s welfare , but clearly the baby felt pain .
According to a 2005 study , not even intravenously administered morphine can block the pain of a heel stick in premature newborns .
A 2009 Italian study reported : “ Scientific research in recent years has continued to confirm that neonates , especially when preterm , are more sensitive ” to pain @ @ @ @ @ @ @ American study noted that “ preterm infants have demonstrated an exaggerated acute response to pain ” compared to babies born at full term .
So barring very rare neurological conditions , premature newborns can definitely feel pain .
Let ’ s work backwards from there .
How Young Can a Human Be and Still Survive Premature Birth ?
Recall from Part One that pregnancy is normally measured from the first day of the last ≈ ( gestational age ) .
The gestational age at which a newborn has a 50 percent chance of @ @ @ @ @ @ @ viability.
” In 2015this age was estimated to be 23 to 24 weeks in developed countries where good intensive care nurseries are available .
( In less developed countries the age of viability was up to 34 weeks . )
Thanks to technological improvements , in 2018 the age of viability was lowered to 22 to 23 weeks ( gestational age ) .
In other words , a fetus has a 50 percent chance of surviving by 20 weeks ( ≈ ) .
I have seen no evidence that passage through the birth @ @ @ @ @ @ @ to perceive pain .
So the available evidence clearly shows that a 20-week-old fetus can feel pain .
Indeed , pain might be felt even earlier : Anesthesiologists who participate in fetal surgeries report that “ a physiological fetal reaction to painful stimuli ” occurs from 16 weeks ( gestational age ) on .
But this is indirect evidence .
By observing premature babies directly we know — as well as we know anything in science — that a fetus can feel pain by the time it is 20 weeks old ( fetal @ @ @ @ @ @ @ contains graphic descriptions that some people may find disturbing .
Reader discretion is advised .
In 2019 , the pro-abortion Guttmacher Institute published a report on the incidence of abortion in the United States in 2017 .
According to the report , abortions in the U.S. have declined in recent years ( probably due to increased access to contraceptives ) , yet in 2017 an estimated 862,320 abortions were provided in clinical settings .
( That ’ s a nationwide average of 2,363 per day , or one about every six minutes .
@ @ @ @ @ @ @ medication abortions.
” The “ abortion pill ” is actually two pills .
The first , mifepristone , prevents the embryo from receiving any nourishment from the mother , and the embryo dies as a result .
The second pill , misoprostol , is taken within 48 hours and induces contractions that expel the dead embryo from the mother ’ s uterus .
The U.S. Food and Drug Administration ( FDA ) is responsible for ( among other things ) testing medicines and approving or disapproving them for use in human beings .
@ @ @ @ @ @ @ humans in 2000 .
According to the U.S. National Institutes of Health , as of July 2020 , the FDA had not officially approved misoprostol for abortions .
Nevertheless , in 2016 the FDA announced that mifepristone “ is approved , in a regimen with misoprostol , to end a pregnancy through 70 days gestation.
” So misoprostol is widely used “ off-label ” along with mifepristone to induce abortion early in pregnancy .
According to Planned Parenthood , the largest abortion provider in the U.S. , the combination is more than 90 @ @ @ @ @ @ @ week of gestation .
From the tenth week through the sixteenth week of gestation , abortions are commonly performed in-clinic by “ dilatation and curettage , ” or D & C .
In this procedure the cervix is dilated ( “ dilatated ” ) , and a thin tube connected to a suction device is inserted into the uterus .
According to Planned Parenthood , “ the pregnancy tissue ” ( a euphemism for the fetus and placenta ) is then sucked out , and a surgical tool called a “ curette ” @ @ @ @ @ @ @ parts .
From the sixteenth week of gestation onward , abortions are commonly performed ( again in-clinic ) by “ dilatation and evacuation , ” or D & E .
The fetus is now too big to be merely scraped and sucked out .
Planned Parenthood describes a D & E as the “ use [ of ] a combination of medical tools and a suction device to gently take the pregnancy tissue out of your uterus.
” As above , “ pregnancy tissue ” is a euphemism for the fetus and placenta @ @ @ @ @ @ @ to the experience of the mother , who is typically sedated or anesthetized during the procedure , but it certainly does not describe what is happening to the fetus .
The “ medical tools ” used in a D & E include forceps such as a “ Sopher clamp , ” an instrument that is about a foot long and made of stainless steel .
According to a doctor who used to perform D & Es , “ At one end are located jaws about 2 inches long and about [ half ] @ @ @ @ @ @ @ ridges or teeth .
This instrument is for grasping and crushing tissue.
” After the mother ’ s cervix has been dilated , the person performing the abortion inserts the Sopher clamp into her uterus , grabs whatever part of the fetus is closest ( often an arm or a leg ) , and pulls hard until it comes loose .
The part is then removed or suctioned from the uterus , and the process is continued until all parts of the fetus have been taken out .
The pieces are set aside @ @ @ @ @ @ @ parts of the fetus have been evacuated .
In 2015 , a controversy arose over Planned Parenthood ’ s practice of charging for aborted baby parts to be used in research .
Critics claimed the practice violated federal law , while the organization claimed it was merely recovering costs and not making a profit .
An undercover video made in 2014 showed two senior Planned Parenthood officials discussing the matter .
When asked whether the method of abortion would be modified for babies who had been earmarked ahead of time for organ harvesting @ @ @ @ @ @ @ ) that they might use “ a less crunchy technique to get more whole specimens.
” According to the authors of a 2020 article titled “ Reconsidering Fetal Pain , ” a “ D & E procedure… may involve fetal pain before fetal death.
” Sometimes the fetus is killed first by lethal injection ( “ feticide ” ) , but sometimes not .
In a D & E , the authors wrote , “ the fetus is removed in pieces via several surgical manoeuvres using grasping forceps… [ F ] etal death @ @ @ @ @ @ @ D & E or the trauma of the D & E results in the death of the fetus.
” The authors did not propose banning D & Es , but they recommended using anesthesia beforehand .
A 2019 U.S. Centers for Disease Control study based on 2016 abortions in the U.S. concluded that 91.0 percent of abortions were performed up to 13 weeks ’ gestation , 7.7 percent of abortions were performed at 14–20 weeks ’ gestation , and 1.2 percent were performed after 21 weeks ’ gestation .
Applying those percentages to @ @ @ @ @ @ @ U.S. abortions in 2017 , 14,659 fetuses older than 21 weeks were aborted that year , presumably by D & E .
That ’ s an average of 28 per day , or more than one every hour .
A few years ago , Montana State Representative ( and orthopedic surgeon ) Albert Olszewski introduced legislation that would require doctors to give fetuses older than 20 weeks painkillers before aborting them .
By the time it passed it had been amended to allow mothers to forgo fetal anesthesia if they gave informed consent @ @ @ @ @ @ @ law , however .
Montana Governor Steve Bullock vetoed it .
In the debates before the bill was passed by the legislature the Washington Post reported that Montana State Representative Jenny Eck said : “ I ’ m sorry if women ’ s bodies get in the way of some people ’ s political beliefs… I ’ m sorry that women have autonomy , self-determination and constitutional rights .
But that ’ s the way it is .
And until men can carry babies or artificial incubators can build babies , you ’ @ @ @ @ @ @ @ women have our own rights , our own lives , our own wills.
” Apparently , for Representative Eck , those include the right to dismember an unborn human being who can feel pain .
There are reports that hundreds of babies have been born alive after failed abortion attempts .
Two of the best-known cases involve Ana Rosa Rodriquez and Nik Hoot .
Ana Rosa Rodriguez was born alive in New York in October 1991 .
She was a healthy little girl , except that she was missing her right arm .
@ @ @ @ @ @ @ D & E that failed because her mother had gone into labor in the middle of the attempted abortion .
The doctor who performed the procedure was subsequently convicted of violating a New York law that prohibited abortions after 24 weeks .
Nik Hoot was born alive in Russia on September 19 , 1996 .
He , too , was a victim of a failed D & E .
Before his premature birth at 24 weeks , his left foot and most of his right leg had been torn off , along with @ @ @ @ @ @ @ .
An American couple adopted him a year later .
One of his parents later said : “ Personal liberties are one thing , but not at the cost of physical damage and pain to another human which limits their ability to pursue life , liberty and happiness.
” Amazingly , Nik overcame his partial dismemberment and became an inspiration to others .
He eventually made the news as a varsity wrestler at an Indiana high school .
With the help of prosthetic legs , he also played baseball , football , and @ @ @ @ @ @ @ 2013 , Nik said : “ I knew that I was supposed to be an aborted baby and it failed .
It makes me angry because I would never want for that to happen to any kid… I just look at myself as a miracle .
”

Photo credit: Fibonacci Blue / CC BY (https://creativecommons.org/licenses/by/2.0).
Editor’s note: See also Dr. Wells’s earlier article, “Why Should a Baby Live?”
This is Part Two of a two-part series about abortion. This part focuses on the second question I raised in Part One: At what point in its development can a human being feel pain? I will attempt to answer the question scientifically, as a developmental biologist. By “scientific” I mean based on evidence, not on materialistic story-telling or the current “scientific consensus.” I will conclude with a brief personal reflection.
The title of my first essay was “Why Should a Baby Live?” It was adapted from a 2012 article by Alberto Giubilini and Francesca Minerva, “After-birth abortion: why should the baby live?” That article cites a 1985 book co-authored by Peter Singer titled Should the Baby Live? Ten years before, Singer had published his seminal work, Animal Liberation. In that book he wrote: “The Darwinian revolution was genuinely revolutionary. Human beings now knew that they were not the special creation of God, made in the divine image and set apart from the animals; on the contrary, human beings came to realize that they were animals themselves.” (p. 214) Singer argued that animals, like humans, deserve protection because of their ability to suffer. The fact that they cannot speak is irrelevant. We cannot refuse “to attribute pain to those who do not have language… Human infants and young children are unable to use language. Are we to deny that a year-old child can suffer? If not, language cannot be crucial.” (p. 15)
Giubilini and Minerva flipped the logic of the Catholic belief that “fetuses and newborns share the same moral status” to argue that because “abortion is largely accepted,” newborns (like fetuses) do not have a right to life. But I would flip Peter Singer’s logic: If we cannot deny that a year-old child can feel pain, how are we to deny that a fetus can feel pain?
Logic isn’t a sufficient answer to the question I raised, however. For a scientific answer, we need evidence.
At What Point Can a Human Fetus Feel Pain?
If I gently poke a living cell in a Petri dish, it may recoil from the stimulus. But people don’t usually call that “pain.” Dictionary definitions differ, but they generally include (1) physical and emotional distress due to injury or disease; (2) mediation through nerve impulses to the brain; and (3) aversive action. Only the last of these is exhibited by the cell in the Petri dish.
If pain requires the transmission of nerve impulses to the brain, then a human embryo (up to eight weeks post-fertilization) probably cannot feel pain. (NOTE: I am not arguing that this justifies abortion before eight weeks, only that we cannot say that an embryo feels pain in the full sense of the word.) After eight weeks embryonic age (ten weeks gestational age), a developing human being is called a fetus. Unfortunately, it is not currently possible to establish the point at which the fetus can feel pain by working forward from the eight-week stage. So let’s start by working backwards.
From 1964 to 1998 I worked periodically as a clinical laboratory technologist. One of my responsibilities was to collect blood samples from two-to-three-day-old newborns. The samples were used to test for phenylketonuria (PKU), an inherited disorder that can occur in as many as 1 out of every 10,000 births. A baby with PKU cannot properly metabolize the amino acid phenylalanine, a necessary nutrient in the human diet. The result is a build-up of toxin that can lead to severe mental impairment, among other things. If PKU is detected early, however, the child can be fed a special diet that contains only the minimum amount of phenylalanine, and mental impairment can be prevented.
I would routinely collect a drop of blood from a newborn — even if it was premature — by sticking a small, sterile metal blade into its heel. That blood was used to test for PKU. Every time I did this, however, the newborn would scream at the top of his or her tiny lungs, and it would jerk spasmodically in the only aversive activity of which it was capable. I did it for the baby’s welfare, but clearly the baby felt pain.
According to a 2005 study, not even intravenously administered morphine can block the pain of a heel stick in premature newborns. A 2009 Italian study reported: “Scientific research in recent years has continued to confirm that neonates, especially when preterm, are more sensitive” to pain than older children. And a 2016 American study noted that “preterm infants have demonstrated an exaggerated acute response to pain” compared to babies born at full term.
So barring very rare neurological conditions, premature newborns can definitely feel pain. Let’s work backwards from there.
How Young Can a Human Be and Still Survive Premature Birth?
Recall from Part One that pregnancy is normally measured from the first day of the last menstrual period (gestational age). The gestational age at which a newborn has a 50 percent chance of surviving is called the “age of viability.” In 2015 this age was estimated to be 23 to 24 weeks in developed countries where good intensive care nurseries are available. (In less developed countries the age of viability was up to 34 weeks.) Thanks to technological improvements, in 2018 the age of viability was lowered to 22 to 23 weeks (gestational age). In other words, a fetus has a 50 percent chance of surviving by 20 weeks (fetal age).
I have seen no evidence that passage through the birth canal jumpstarts a human’s ability to perceive pain. So the available evidence clearly shows that a 20-week-old fetus can feel pain. Indeed, pain might be felt even earlier: Anesthesiologists who participate in fetal surgeries report that “a physiological fetal reaction to painful stimuli” occurs from 16 weeks (gestational age) on. But this is indirect evidence. By observing premature babies directly we know — as well as we know anything in science — that a fetus can feel pain by the time it is 20 weeks old (fetal age).
Abortion Incidence and Procedures — Before 16 Weeks
WARNING: What follows contains graphic descriptions that some people may find disturbing. Reader discretion is advised.
In 2019, the pro-abortion Guttmacher Institute published a report on the incidence of abortion in the United States in 2017. According to the report, abortions in the U.S. have declined in recent years (probably due to increased access to contraceptives), yet in 2017 an estimated 862,320 abortions were provided in clinical settings. (That’s a nationwide average of 2,363 per day, or one about every six minutes.) About 339,640 of these were “medication abortions.”
The “abortion pill” is actually two pills. The first, mifepristone, prevents the embryo from receiving any nourishment from the mother, and the embryo dies as a result. The second pill, misoprostol, is taken within 48 hours and induces contractions that expel the dead embryo from the mother’s uterus.
The U.S. Food and Drug Administration (FDA) is responsible for (among other things) testing medicines and approving or disapproving them for use in human beings. It approved mifepristone for obstetric use in humans in 2000. According to the U.S. National Institutes of Health, as of July 2020, the FDA had not officially approved misoprostol for abortions. Nevertheless, in 2016 the FDA announced that mifepristone “is approved, in a regimen with misoprostol, to end a pregnancy through 70 days gestation.” So misoprostol is widely used “off-label” along with mifepristone to induce abortion early in pregnancy. According to Planned Parenthood, the largest abortion provider in the U.S., the combination is more than 90 percent effective if used by the tenth week of gestation.
From the tenth week through the sixteenth week of gestation, abortions are commonly performed in-clinic by “dilatation and curettage,” or D&C. In this procedure the cervix is dilated (“dilatated”), and a thin tube connected to a suction device is inserted into the uterus. According to Planned Parenthood, “the pregnancy tissue” (a euphemism for the fetus and placenta) is then sucked out, and a surgical tool called a “curette” is used to scrape out any remaining parts.
Abortion Incidence and Procedures — After 16 Weeks
From the sixteenth week of gestation onward, abortions are commonly performed (again in-clinic) by “dilatation and evacuation,” or D&E. The fetus is now too big to be merely scraped and sucked out. Planned Parenthood describes a D&E as the “use [of] a combination of medical tools and a suction device to gently take the pregnancy tissue out of your uterus.” As above, “pregnancy tissue” is a euphemism for the fetus and placenta. And “gently” may apply to the experience of the mother, who is typically sedated or anesthetized during the procedure, but it certainly does not describe what is happening to the fetus.
The “medical tools” used in a D&E include forceps such as a “Sopher clamp,” an instrument that is about a foot long and made of stainless steel. According to a doctor who used to perform D&Es, “At one end are located jaws about 2 inches long and about [half] an inch wide with rows of sharp ridges or teeth. This instrument is for grasping and crushing tissue.” After the mother’s cervix has been dilated, the person performing the abortion inserts the Sopher clamp into her uterus, grabs whatever part of the fetus is closest (often an arm or a leg), and pulls hard until it comes loose. The part is then removed or suctioned from the uterus, and the process is continued until all parts of the fetus have been taken out. The pieces are set aside so an inventory can determine whether all parts of the fetus have been evacuated.
In 2015, a controversy arose over Planned Parenthood’s practice of charging for aborted baby parts to be used in research. Critics claimed the practice violated federal law, while the organization claimed it was merely recovering costs and not making a profit. An undercover video made in 2014 showed two senior Planned Parenthood officials discussing the matter. When asked whether the method of abortion would be modified for babies who had been earmarked ahead of time for organ harvesting, one official suggested (at 6:10) that they might use “a less crunchy technique to get more whole specimens.”
According to the authors of a 2020 article titled “Reconsidering Fetal Pain,” a “D&E procedure… may involve fetal pain before fetal death.” Sometimes the fetus is killed first by lethal injection (“feticide”), but sometimes not. In a D&E, the authors wrote, “the fetus is removed in pieces via several surgical manoeuvres using grasping forceps… [F]etal death follows either direct feticide performed before the D&E or the trauma of the D&E results in the death of the fetus.” The authors did not propose banning D&Es, but they recommended using anesthesia beforehand.
A 2019 U.S. Centers for Disease Control study based on 2016 abortions in the U.S. concluded that 91.0 percent of abortions were performed up to 13 weeks’ gestation, 7.7 percent of abortions were performed at 14–20 weeks’ gestation, and 1.2 percent were performed after 21 weeks’ gestation. Applying those percentages to the Guttmacher Institute’s report on U.S. abortions in 2017, 14,659 fetuses older than 21 weeks were aborted that year, presumably by D&E. That’s an average of 28 per day, or more than one every hour.
A few years ago, Montana State Representative (and orthopedic surgeon) Albert Olszewski introduced legislation that would require doctors to give fetuses older than 20 weeks painkillers before aborting them. By the time it passed it had been amended to allow mothers to forgo fetal anesthesia if they gave informed consent. The bill never made it into law, however. Montana Governor Steve Bullock vetoed it.
In the debates before the bill was passed by the legislature the Washington Post reported that Montana State Representative Jenny Eck said: “I’m sorry if women’s bodies get in the way of some people’s political beliefs… I’m sorry that women have autonomy, self-determination and constitutional rights. But that’s the way it is. And until men can carry babies or artificial incubators can build babies, you’re stuck with that reality: that women have our own rights, our own lives, our own wills.”
Apparently, for Representative Eck, those include the right to dismember an unborn human being who can feel pain.
Concluding Personal Reflection
There are reports that hundreds of babies have been born alive after failed abortion attempts. Two of the best-known cases involve Ana Rosa Rodriquez and Nik Hoot. Ana Rosa Rodriguez was born alive in New York in October 1991. She was a healthy little girl, except that she was missing her right arm. It had been torn off during a D&E that failed because her mother had gone into labor in the middle of the attempted abortion. The doctor who performed the procedure was subsequently convicted of violating a New York law that prohibited abortions after 24 weeks.
Nik Hoot was born alive in Russia on September 19, 1996. He, too, was a victim of a failed D&E. Before his premature birth at 24 weeks, his left foot and most of his right leg had been torn off, along with parts of his fingers on both hands. An American couple adopted him a year later. One of his parents later said: “Personal liberties are one thing, but not at the cost of physical damage and pain to another human which limits their ability to pursue life, liberty and happiness.”
Amazingly, Nik overcame his partial dismemberment and became an inspiration to others. He eventually made the news as a varsity wrestler at an Indiana high school. With the help of prosthetic legs, he also played baseball, football, and basketball. In a televised interview in 2013, Nik said: “I knew that I was supposed to be an aborted baby and it failed. It makes me angry because I would never want for that to happen to any kid… I just look at myself as a miracle.”
That’s why a baby should live.


evolutionnewsandviews--2020-09-21--Kimberella Is No Solution to the Cambrian Conundrum

Editor ’ s note : We have been delighted to present a series of posts by paleontologist Günter Bechly on the Ediacaran organism Kimberella .
If identified as an animal , it would “ predate the Cambrian explosion of bilaterian animal phyla as a kind of ‘ advance guard.
’ ” The question is of interest for debates about evolution and arguments about intelligent design raised by Stephen Meyer , among others .
Find the full series about Kimberella here .
We can sum up that the current consensus suggests : that Kimberella is indeed a metazoan animal and most @ @ @ @ @ @ @ of Bilateria or maybe has an uncertain position within Lophotrochozoa , but it is not a stem mollusk .
Nevertheless , the proper interpretation of many of the structures of Kimberella is still controversial and the alternative possibility that Kimberella could be a coelenterate grade animal can not be ruled out yet , especially since there is evidence for sclerotization and very diverse body plans in early Cambrian comb jellies ( Scleroctenophora ) ( Zhao et al .
2019 ) , as well as evidence for ancestral bilateral symmetry in Cnidaria ( Erwin @ @ @ @ @ @ @ us about the Cambrian explosion ?
Together with the alleged evidence for other Ediacaran bilaterian animals , which we critically discussed in my previous articles , this means that none of the Cambrian animal phyla is represented in the Ediacaran fossil record .
This is very significant , because the potential soft-bodied ancestors would surely have been preserved in the numerous Ediacaran fossil localities of the Burgess Shale type ( Bechly 2020 ) , or in the Kimberella layers , which after all could preserve the soft-parts of a mollusk-like organism .
At @ @ @ @ @ @ @ bilaterians , Kimberella and the recently described worm-like Yilingia ( Chen et al .
2019 , Evolution News 2019 ) , could document the existence of just two phyla of Bilateria of uncertain affinity prior to the Cambrian era .
However , their unique specializations strongly suggest that they could only represent extinct side branches but could not be directly ancestral to any of the numerous Cambrian animal phyla , and thus do not resolve their enigmatic origin .
Therefore , the latter still appear abruptly out of nowhere .
The thousands of @ @ @ @ @ @ @ s theory of evolution , for the transition from a protist choanoflagellate ancestor to the complex body plans of the more than twenty Cambrian phyla of bilaterian metazoan animals , still remain elusive and missing , in spite of suitable fossil localities .
Actually , the same problem exists for the so-called Avalon explosion that abruptly generated the diversity of macro-organisms of the Ediacaran biota .
Where are all the missing links for the problematic organisms like Charnia , Dickinsonia , and Kimberella , which would document their gradual and stepwise evolution from @ @ @ @ @ @ @ any longer ignore this substantial conflicting evidence .
The fossil record speaks clearly and cries out loud : the history of life on Earth is a history of saltations .
There is a reason why scientists called these abrupt appearances “ explosions ” or even “ Big Bangs ” of life .
Guess which model better fits this evidence , Darwin ’ s theory of gradually “ climbing mountain improbable ” ( a metaphor offered by Richard Dawkins ) or rather intelligent design theory ?
It is not a difficult choice , unless @ @ @ @ @ @ @ theories are allowed .
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Photo: Kimberella, by Ghedoghedo / CC BY-SA (https://creativecommons.org/licenses/by-sa/3.0).
Editor’s note: We have been delighted to present a series of posts by paleontologist Günter Bechly on the Ediacaran organism Kimberella. If identified as an animal, it would “predate the Cambrian explosion of bilaterian animal phyla as a kind of ‘advance guard.’” The question is of interest for debates about evolution and arguments about intelligent design raised by Stephen Meyer, among others. Find the full series about Kimberella here.
We can sum up that the current consensus suggests: that Kimberella is indeed a metazoan animal and most probably belongs either in the stem group of Bilateria or maybe has an uncertain position within Lophotrochozoa, but it is not a stem mollusk. Nevertheless, the proper interpretation of many of the structures of Kimberella is still controversial and the alternative possibility that Kimberella could be a coelenterate grade animal cannot be ruled out yet, especially since there is evidence for sclerotization and very diverse body plans in early Cambrian comb jellies (Scleroctenophora) (Zhao et al. 2019), as well as evidence for ancestral bilateral symmetry in Cnidaria (Erwin 2008).
Implications for the Cambrian Explosion
What does this tell us about the Cambrian explosion? Together with the alleged evidence for other Ediacaran bilaterian animals, which we critically discussed in my previous articles, this means that none of the Cambrian animal phyla is represented in the Ediacaran fossil record. This is very significant, because the potential soft-bodied ancestors would surely have been preserved in the numerous Ediacaran fossil localities of the Burgess Shale type (Bechly 2020), or in the Kimberella layers, which after all could preserve the soft-parts of a mollusk-like organism. At best the only two relatively uncontroversial Ediacaran bilaterians, Kimberella and the recently described worm-like Yilingia (Chen et al. 2019, Evolution News 2019), could document the existence of just two phyla of Bilateria of uncertain affinity prior to the Cambrian era. However, their unique specializations strongly suggest that they could only represent extinct side branches but could not be directly ancestral to any of the numerous Cambrian animal phyla, and thus do not resolve their enigmatic origin.
Therefore, the latter still appear abruptly out of nowhere. The thousands of fossil links, postulated by Darwin’s theory of evolution, for the transition from a protist choanoflagellate ancestor to the complex body plans of the more than twenty Cambrian phyla of bilaterian metazoan animals, still remain elusive and missing, in spite of suitable fossil localities. Actually, the same problem exists for the so-called Avalon explosion that abruptly generated the diversity of macro-organisms of the Ediacaran biota. Where are all the missing links for the problematic organisms like Charnia, Dickinsonia, and Kimberella, which would document their gradual and stepwise evolution from protozoan ancestors?
Honest scientists cannot any longer ignore this substantial conflicting evidence. The fossil record speaks clearly and cries out loud: the history of life on Earth is a history of saltations. There is a reason why scientists called these abrupt appearances “explosions” or even “Big Bangs” of life. Guess which model better fits this evidence, Darwin’s theory of gradually “climbing mountain improbable” (a metaphor offered by Richard Dawkins) or rather intelligent design theory? It is not a difficult choice, unless your world view dictates what kind of theories are allowed.
References


evolutionnewsandviews--2020-09-20--Tour, Meyer on the Multiverse, and More

Tour, Meyer on the Multiverse, and More

On a new episode of ID the Future , Rice University synthetic organic chemist and inventor James M. Tour continues @ @ @ @ @ Meyer , director of the Center for Science & Culture .
Download the podcast or @ @ @ @ @ In this third of three episodes featuring the two researchers , Tour draws from questions @ @ @ @ @ his own podcast .
These include questions about the multiverse , quantum cosmology , the @ @ @ @ @ — of life on other planets , the Big Bang , and what intelligent design @ @ @ @ @ viruses and bacteria .
The episode is excerpted from an extended interview from Tour ’ @ @ @ @ @ The Science & Faith Podcast : Follow the Evidence .
There you will find the @ @ @ @ @ form as well as episodes featuring Henry F. Schaeffer III , John Lennox , and @ @

Photo credit: ESA/Hubble & NASA, M. Gregg.
On a new episode of ID the Future, Rice University synthetic organic chemist and inventor James M. Tour continues his conversation with Stephen C. Meyer, director of the Center for Science & Culture. Download the podcast or listen to it here. In this third of three episodes featuring the two researchers, Tour draws from questions sent in by listeners to his own podcast. These include questions about the multiverse, quantum cosmology, the possibility — and theological implications — of life on other planets, the Big Bang, and what intelligent design thinking has to say about viruses and bacteria.
The episode is excerpted from an extended interview from Tour’s excellent new video series The Science & Faith Podcast: Follow the Evidence. There you will find the full Meyer interview in video form as well as episodes featuring Henry F. Schaeffer III, John Lennox, and others.