In Radio Debate, Darwin's Doubt Critic Charles Marshall Acknowledges Meyer's Fossil Treatment Is "Good Scholarship"
There are two competing paradigms about Neanderthal capabilities and culture. The first considers Neanderthals to be cognitively inflexible, with a limited use of technologies that was unresponsive to environmental change. The second recognises a much wider range of behaviours and technologies, with adaptation to specific local conditions. The paper considered in this blog belongs to the second of these perspectives: the reported work considers artefacts from a cave that was occupied by Neanderthals and dated about 90,000 years ago.
"Here, we present evidence for behavioral variability and complexity among Neanderthals at the beginning of Marine Isotope Stage 4 (MIS 4) at the Abri du Maras located above the Ardeche River in southern France. Using residue analysis of stone tools with supporting evidence from zooarchaeology, we show that Neanderthals at the Abri du Maras had a detailed knowledge of their surrounding environment, captured fast and agile prey (rabbits, fish and birds), exploited a range of plant species, and used composite technology such as hafted stone points and the manufacture of string and cordage. Overall, we present evidence which demonstrates that Neanderthals at the Abri du Maras were far from inefficient foragers." (p.24)
Not just a pretty face (Image: Nikola Solic/Reuters, source here))
Many flake stone tools have been recovered. Microscopic examination of their surfaces has revealed a remarkable variety of traces providing clues about Neanderthal capabilities and lifestyle. The most noteworthy relates to tiny fragments of twisted plant fibres. This is considered to be evidence for human activity: gathering plant material, retting or shredding to extract fibres, twisting to create threads or string, and cutting a length with the stone tools.
"These fibers are not twisted in their natural state which suggests that they were twisted by the inhabitants of the Abri du Maras and may therefore provide evidence of the manufacture of string or cordage. In previous woodworking experiments involving incising, planning, whittling, scraping, and boring, no twisted fibers were observed. Unpublished experiments conducted by BH involving the scraping, cutting, and slicing of a variety of nonwoody plants (roots, tubers, reeds, etc.) also produced no twisted fibers such as those observed here. While not definitive, the lack of twisted fibers in these experiments lends some credence to the hypothesis that these derive from cordage. Future experiments involving cordage and plant processing will help clarify the potential sources of twisted fiber." (p.27,29)
Circumstantial evidence is provided by observations of micro-wear of flake tools that show indications of being hafted to produce stone-tipped javelins. Other uses for string can be inferred because there is evidence at this site that Neanderthals went fishing and at other sites that they crossed open water in boats.
"Since macroscopic remains have not been found prior to 19 ka, it is important to examine other less direct forms of evidence where fiber or string production may leave traces on a microscopic level which may be visible through use-wear and residue analyses. For most of the Paleolithic, the best potential source of evidence for cordage is stone tools. Hurcombe (1998) describes several different points in the chaine operatoire of fiber production where stone tools are likely to be used, including plant harvesting, processing of fibers, and cutting loose ends from cordage.
The production of string along with simple knowledge of knotting, weaving, and looping, make possible a wide range of products including "nets, containers, packaging, baskets, carrying devices, ties, straps, harness, clothes, shoes, beds, bedding, mats, flooring, roofing and walling". In addition, string facilitates the construction of complex, multi-component technologies such as hafts or snares. Finally, string would have been essential for seafaring, maritime technologies used for the colonization of islands, and for many types of fishing." (p.34)
We cannot consider all the evidences discussed by the authors. However, they make an interesting comment on how expectations (influenced by presuppositions) affect research programmes.
"Paleolithic archaeologists have a tendency to focus heavily on reconstructing subsistence activities. Within subsistence, the focus is primarily on animals with even more narrow focus on large animals, partly because their remains preserve better. This focus is justified to some extent as archeologists can only work with the evidence they find. However, this means we are missing a huge component of everyday life. The preservation bias of the archaeological record limits the avenues being investigated. The fiber evidence presented here is a reminder that if we don?t look for it, we won?t find it." (p.35)
We shall pass over much interesting discussion of evidences and reach their conclusion. The authors have used their detective skills to reconstruct a community of Neanderthals that appears to be indistinguishable from modern humans.
"The Abri du Maras overlooks the Ardeche River in south-eastern France. The combination of analyses presented here (mainly residue analysis) has provided a more detailed view into Neanderthal lives than is generally possible. Neanderthals at the Abri du Maras caught and consumed a wide variety of foods, from large herbivores to rabbits, fish, plants, and possibly birds. The occupants of the Abri du Maras may have also been engaged in a variety of other activities: gathering mushrooms, gathering raw materials and manufacturing string, woodworking, constructing composite technologies such as complex projectiles and possibly nets or traps. Given the wide variety of resources exploited at the Abri du Maras, we should heed Hockett's recent caution that we may have "under-appreciated the amount of non-mammal foods eaten by Neanderthals". We would add that the high diversity of resources used by Neanderthals has been generally under-appreciated for decades." (p.38)
This fascinating insight into community life is worthy of our attention because the group members were Neanderthals. For too long, they have been portrayed as pre-human and have been used to buttress evolutionary stories about the origins of mankind. However, archaeological evidence discussed here (and here) suggests that these stories are embellished with evolutionary spin. The evidence shows that Neanderthals are human cousins and deserve quite a different place in history. Unfortunately, this truth about Neanderthals has been missed in the past because the presumption of evolutionary transformation has constrained the minds of researchers. They illustrate the maxim: "if we don't look for it, we won't find it."
Impossible Neanderthals? Making string, throwing projectiles and catching small game during Marine Isotope Stage 4 (Abri du Maras, France)
Bruce L. Hardy, Marie-Helene Moncel, Camille Daujeard, Paul Fernandes, Philippe Bearez, Emmanuel Desclaux, Maria Gema Chacon Navarro, Simon Puaud, Rosalia Gallotti
Quaternary Science Reviews, Volume 82, 15 December 2013, Pages 23?40
Abstract: Neanderthal behavior is often described in one of two contradictory ways: 1) Neanderthals were behaviorally inflexible and specialized in large game hunting or 2) Neanderthals exhibited a wide range of behaviors and exploited a wide range of resources including plants and small, fast game. Using stone tool residue analysis with supporting information from zooarchaeology, we provide evidence that at the Abri du Maras, Ardeche, France, Neanderthals were behaviorally flexible at the beginning of MIS 4. Here, Neanderthals exploited a wide range of resources including large mammals, fish, ducks, raptors, rabbits, mushrooms, plants, and wood. Twisted fibers on stone tools provide evidence of making string or cordage. Using a variety of lines of evidence, we show the presence of stone projectile tips, possibly used in complex projectile technology. This evidence shows a level of behavioral variability that is often denied to Neanderthals. Furthermore, it sheds light on perishable materials and resources that are not often recovered which should be considered more fully in reconstructions of Neanderthal behavior.
I bought a copy of "The Explanation of Everything" by Lauren Grodstein. The book was an interesting read on relationships to be sure, but the ID/atheist debate was as deep as a mountain stream near its source. In the book, one female Christian has sensual urges which she acts out on the professor. Her pastor has a curious theology, at least from a Protestant worldview, which he apparently holds. The quirky male believer does an about fact to atheism. Meantime the atheist professor oddly feels the ghost of his departed wife while still an atheist, and becomes a theist, or should I say, a deist.
I was hoping for more on the debate side...
Read the ENV article by David Klinghoffer.
Earlier this year, in March, Nature reported that soft-bodied worms from the Burgess Shale fossil beds in Canada, given the name Spartobranchus tenuis, have been identified as ancient examples of acorn worms. They were hailed as a "missing link" in the vertebrate family tree: "a crucial evolutionary link between two distinct living groups of animals: enteropneusts and pterobranchs." The evidence supporting this was said to be the tubes constructed by Spartobranchus tenuis. Living enteropneusts (acorn worms) do not have tubes, whereas living pterobranchs (minute colonial organisms) do. Professor Simon Conway Morris affirmed the significance of the newly discovered fossil tubes with these words: "By finding enteropneusts in tubes we begin to bridge this evolutionary gap." At the time, these issues were discussed in a blog here, and questions were raised about the evolutionary narrative. More now needs to be said, as a recent paper in Nature Communications has documented modern tube-forming acorn worms found in Antarctic benthic communities.
Figure 1b: Large purple morphotype in secreted tube with proboscis expanded. (Source here)
Recent work surveying life in ocean basins has identified a new family of deep-sea enteropneusts, the Torquaratoridae. During oceanographic cruises in the Antarctic, between 2008 and 2013, two new enteropneusts were discovered at depths ranging from 531 to 1,111m. These species secrete translucent tubes in which they live, although they have also been observed abandoning their tubes. The authors recognize that their discovery is directly relevant to the interpretation of the Burgess Shale worm tubes. This is their discussion:
"Foremost, our discovery provides context for the recently re-described Middle Cambrian fossils, S. tenuis from the Burgess Shale Formation. These acorn worm fossils look remarkably like present-day enteropneusts, except many are observed to be within a 'fiberous' tube. The persistence of tubes in Antarctic worms suggests that the tubes contain proteinaceous components functioning as binding agents. Some tubes were lightly covered with sediment giving them a 'ribbed' appearance, similar to those reported for S. tenuis. [. . .] Our observations of Antarctic tubicolous worms and faecal casings imply that the worms often turn and zigzag during movement or may even double back on themselves as reported elsewhere. If buried quickly in a single obtrusion event, as suspected for each of the mudstone beds of the Greater Phyllopod Bed (that is, Walcott's quarry), such tubes could appear helical or even circular as reported for S. tenuis [. . .]. The fossil tubes were interpreted as 'fiberous' based on apparent tearing of the tubes, but a similar phenomenon occurs with the present-day tubes. Given the similarity in tube design between S. tenuis and the Antarctic torquaratorids, similar behavioural repertoires (for example, tube building, vacating tubes and meandering epibenthic movements) appear to have been conserved ~500 million years."
So, the discovery of modern tube-forming acorn worms has assisted the interpretation of the fossil tubes: the fibrous texture is an artifact of preservation and not part of the constructed tube, and the doughnut shapes are likely to be formed by a rapid depositional process and is not representative of the original structure in life. The evidence we have is of stasis in behavioral repertoires as well as in morphology.
This leads to a rather different conclusion about the implications for evolutionary theory. The idea that S. tenuis is a link between the enteropneusts and the pterobranchs lacks credibility. The argument is explained very clearly in the research paper:
"Fossil evidence reveals that graptolites, and even rhabopleurids and cephalodiscids (modern pterobranch lineages), were present in the Middle Cambrian, making S. tenuis contemporary with established pterobranch (including graptolite) lineages. As the split between enteropneust and pterobranch lineages would have been before the Middle Cambrian, the tube of S. tenuis was not a precursor to the pterobranch coenecium. Lack of synapticulae and hepatic sacs were also argued to ally S. tenuis with harrimaniid enteropneusts. However, torquaratorid enteropneusts, like harrimaniids, lack synapticles, and assessing the presence of hepatic sacs often requires microscopy in modern species, much less in fossilized ones. Given the position of torquaratorids and pterobranchs in hemichordate phylogeny, the last common hemichordate ancestor may have been able to build tubes, raising the question whether this ability was present in the last common deuterostome ancestor."
The implication is that the last common hemichordate ancestor lived before the Middle Cambrian and should be located before the Cambrian Explosion. The problem for this hypothesis is that there is a paucity of fossil data: we do not have anything other than speculation for hypothetical ancestors of the animal phyla. Instead of evolutionary theory having anchors in fossil evidence about the past, the Precambrian is effectively a blank sheet where inferences are drawn from selected phylogenetic data and produce conflicting evolutionary trees.
There is a pattern in the way fossil discoveries are reported. If they are deemed to fill in the gaps in a branch of the evolutionary tree, they generally get massive exposure and are hailed as milestones in developing an understanding of life on Earth. However, when new data comes to light that shows the original thinking to be wrong, the exposure is far less and the media show little interest. With acorn worms, we have a case to reflect on worthy of our time. The message we should be taking away is that the fossil record brings us evidence of stasis, not evolutionary transformation. We need a radical rethink of the presuppositions we bring to the story of life on Earth, because the present hegemony of Darwinism has no adequate explanation for the origin of biological information.
Modern Antarctic acorn worms form tubes
Kenneth M. Halanych, Johanna T. Cannon, Andrew R. Mahon, Billie J. Swalla and Craig R. Smith
Nature Communications, 4, No. 2738, 07 November 2013 | doi: 10.1038/ncomms3738
Abstract: Acorn worms, or enteropneusts, are vermiform hemichordates that occupy an important position in deuterostome phylogeny. Allied to pterobranch hemichordates, small colonial tube dwellers, modern enteropneusts were thought to be tubeless. However, understanding of hemichordate diversity is poor, as evidenced by absence of reports from some oceanic regions and recent descriptions of large epibenthic deep-water enteropneusts, Torquaratoridae. Here we show, based on expeditions to Antarctica, that some acorn worms produce conspicuous tubes that persist for days. Interestingly, recent fossil descriptions show a Middle Cambrian acorn worm lived in tubes, leading to speculation that these fossils may have been pterobranch forbearers. Our discovery provides the alternative interpretation that these fossils are similar to modern-day torquaratorids and that some behaviours have been conserved for over 500 million years. Moreover, the frequency of Antarctic enteropneusts observed attests to our limited knowledge of Antarctic marine ecosystems, and strengthens hypotheses relating more northern deep-sea fauna to Antarctic shelf fauna.
Birchfield, C. Auburn University researchers make deep sea creature discovery and set sail for Antarctica, Auburn University News, 20 November 2013.