The Bad News Continues With More on European Hominin Lineage
Although there is still debate about how exactly they relate to one another and exactly which species some of them are, there is no comfort to be had from that for Creationists, because what is not in any doubt is that there were species of Homo alive and well 430,000 years ago - some 420,000 years before Creationist superstition says Earth was created, and, although there as yet are no fossils, evidence of tools shows that there were humans or proto-humans living in Britain up to 700,000 years ago.
In fact, there is even less comfort to be had for creationists from the doubts about in which exact taxon the different specimens should be placed, because as one species transitions over time into a descendant species, there is never a point in time where the next generation is a different species to its parents - that only happens in the rare cases of a new species arising by hybridization, or in childish Creationist parodies of the process. As I've said before, to determine the exact point of transition is like trying to determine the exact point at which green becomes yellow or blue becomes green in the following colour continuum. And this gets even more complex because not all features evolve in lockstep, so, for example, modern Homo sapiens teeth could have been present in a hominin with an ancestral tibia - exactly what we would expect from an evolutionary process.
That problem is the essence of a study published last November, which somehow I missed at the time. It concerns the exact position of the 'Boxgrove' fossil in relation to other archaic European hominins, using the large sample of about 29 individuals from the Sima de los Huesos (Pit of Bones) site at Atapuerca, Spain. The fossil found at Boxgrove in Suffolk, UK, is normally placed in the H. heidelbergensis taxon, as indeed are many other fossils, simply because they are not, H. erectus, H. neanderthalensis or H. sapiens.
However, a comparison with the Sima de los Huesos fossils, which were also initially assigned to H. heidelbergensis but have since been reclassified on the basis of DNA analysis as early H. neanderthalensis, shows that 'Boxgrove' has many features in common with them. For example, the Boxgrove incisors fit within the range found at Sima de los Huesos, but the tibia has distinct features which suggests it belongs in a separate taxon.
The study is published, open access, in the Journal of Human Evolution. The research, by an international team of paleoanthropologists which included Professor Chris Stringer an expert in human evolution the Natural History Museum, London, and its significance is explained in the Natural History Museum's new release by Emma Caton:
Piecing together the story of human evolution is an undeniably complex task.The team's open access paper is published in the Journal of Human Evolution:
However, new research has brought us closer to understanding how early humans in Britain may have been related to other European populations over 400,000 years ago.
In the 1990s, part of a lower leg bone and two fossil teeth were unearthed at an archaeological site in Boxgrove, West Sussex.
Dating to around 480,000 years ago during the Middle Pleistocene, the Boxgrove fossils are the oldest human remains discovered in the UK and were identified as most likely belonging to the ancient human species Homo heidelbergensis.
Scientists are now trying to determine if the Boxgrove humans belong to the same population as other early human fossils discovered at Sima de los Huesos (meaning 'pit of bones') at the Archaeological site of Atapuerca in Spain, which date to a similar time period.
The new study, published in the Journal of Human Evolution, found that the incisor teeth from Boxgrove fit comfortably within the range of fossil teeth found at the Sima site in Spain. Therefore, they could potentially represent similar populations. However, the Boxgrove leg bone, or tibia, differed significantly from those discovered in Spain, suggesting it could be from entirely separate populations.We've got two options. First, suppose the Boxgrove incisors and tibia are from the same population. In that case, they belong to a different population than the sample in Spain because the Boxgrove tibia has more primitive features. However, because the Boxgrove incisors were found lower and therefore earlier in the sequence of deposits than the tibia, the other option is that those individuals at Boxgrove represent two different populations. In other words, the incisors at Boxgrove and Sima could represent the same population, but the Boxgrove tibia people are different. So that's the issue.
The whole heidelbergensis story has become much more complicated. Since the Boxgrove discovery, many more fossils have been attributed to heidelbergensis and they show a lot of variation. When the fossils at Sima de los Huesos started to be found in the 1990s, they were also called Homo heidelbergensis.
If a fossil didn't appear to belong to Homo erectus, Homo sapiens or Neanderthals, it was often placed into the category of Homo heidelbergensis. But more work has since been done on the Sima sample, which showed it was much more likely to be early Neanderthal based on physical features and DNA analysis.
Trying to piece together how human populations were similar during the Middle Pleistocene is tricky as fossils are very rare and scattered. It's hard to piece the evidence together when we’re trying to match a jawbone from Germany with a leg bone from Britain.
The sample of fossil humans from Spain is by far the biggest from this time period from anywhere in the world. So we can compare the two incisors and tibia from Boxgrove with the 22 incisors and seven tibiae from the Sima sample. We found that the Boxgrove incisors fitted within the Sima sample comfortably, and hence might also represent an early Neanderthal population rather than heidelbergensis, but the tibia did not match with those from the Sima. Hence the tibia is something different, but whether it represents heidelbergensis or something else, we cannot tell from this research.
Professor Chris Stringer, co-author
Centre for Human Evolution Research
Natural History Museum, London, UK
What is Homo heidelbergensis?Four human species are represented here (H. erectus, H. heidelbergensis, H. neanderthalensis, H. sapiens).Image © The Trustees of the Natural History Museum, London
Homo heidelbergensis is a species of early human first described from a fossil jawbone discovered near Heidelberg in Germany in 1907. It’s often argued that this species not only lived in Europe but also in Africa and probably Asia between 700,000 and 300,000 years ago. However, some researchers feel that the name has been applied to too wide a range of fossils from this period of time.
The discovery of stone tools more than 700,000 years old from sites in Suffolk and Norfolk shows that humans were living in Britain long before those from Boxgrove. However, the Boxgrove fossils are the earliest human remains in Britain for which there is currently physical rather than archaeological evidence. But trying to define whether they belong to H. heidelbergensis is not easy.
How were the fossils analysed?
To determine the relationship between the fossils, the team studied external features and used CT scanning for a more in-depth analysis.
Advances in the field of 3D imaging and virtual reconstruction analysis over the last few years has helped to further our knowledge of fossil teeth and bone morphology and structure across the complex Middle Pleistocene hominin fossil record. CT data acquired for this study has been essential to compare the Boxgrove and Sima de los Huesos fossils and other comparative material to help make a coherent story.
Dr Lucile Crété, Corresponding author Centre for Human Evolution Research
Natural History Museum, London, UKSince the discovery of the Boxgrove fossils, more material from the Middle Pleistocene has been analysed in even more detail. However, the story of human evolution and how populations were related has been revealed to be even more complex.This research brings us a step closer to understanding how the Boxgrove people were related to other European populations in the Pleistocene. The picture is complex, given the teeth appear close to those from Sima and the tibia a little more distant. But we must remember that they were found in different sediments at the Boxgrove site. Establishing how separated in time these sediments are from each other is now an important research question for science to address.
Dr Matthew Pope, co-author
Institute of Archaeology
University College London
AbstractJust another example of where real-world evidence is completely at odds with Creationist claims, and yet more evidence that, far from being a theory in Crisis, as Creationists frauds tell their credulous dupes, it is Creationism which is in crisis and destined to join all the other religious superstitions from human history that have been proven to be false. It's consignment to the trash can of history along with all the other primitive supernatural beliefs is long overdue.
The early Middle Pleistocene human material from Boxgrove (West Sussex, UK) consists of a partial left tibia and two lower incisors from a separate adult individual. These remains derive from deposits assigned to the MIS 13 interglacial at about 480 ka and have been referred to as Homo cf. heidelbergensis. The much larger skeletal sample from the Sima de los Huesos (Atapuerca, Spain) is dated to the succeeding MIS 12, at about 430 ka. This fossil material has previously been assigned to Homo heidelbergensis but is now placed within the Neanderthal clade. Because of the scarcity of human remains from the Middle Pleistocene and their morphological variability, this study assessed whether the Boxgrove specimens fit within the morphological variability of the homogeneous Sima de los Huesos population. Based on morphometric analyses performed against 22 lower incisors from Sima de los Huesos and published material, the data from the Boxgrove incisors place them comfortably within the range of Sima de los Huesos. Both assemblages present robust incisors distinct from the overall small recent Homo sapiens incisors, and Boxgrove also aligns closely with Homo neanderthalensis and some other European Middle Pleistocene hominins. Following morphological and cross-sectional analyses of the Boxgrove tibia compared to seven adult Sima de los Huesos specimens and a set of comparative tibiae, Boxgrove is shown to be similar to Sima de los Huesos and Neanderthals in having thick cortices and bone walls, but in contrast resembles modern humans in having a straight anterior tibial crest and a suggestion of a lateral concavity. Based on the patterns observed, there is no justification for assigning the Boxgrove and Sima de los Huesos incisors to distinct paleodemes, but the tibial data show greater contrasts and suggest that all three of these samples are unlikely to represent the same paleodeme.
Lockey, Annabelle L.; Rodríguez, Laura; Martín-Francés, Laura; Arsuaga, Juan Luis; Bermúdez de Castro, José María; Crété, Lucile; Martinón-Torres, María; Parfitt, Simon; Pope, Matt; Stringer, Chris
Comparing the Boxgrove and Atapuerca (Sima de los Huesos) human fossils: Do they represent distinct paleodemes?
Human evolution 172, 103253. DOI: 10.1016/j.jhevol.2022.103253
Copyright: © 2023 The authors.
Published by Elsevier B.V. Open access
Reprinted under a Creative Commons Attribution 4.0 International license (CC BY 4.0)
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