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When studying animal remains from the past, it usually seems like common sense that the more specimens we find, the clearer the details of a lineage becomes. However, it often goes the opposite way in reality: a single specimen or several specimens can often disrupt what may have seemed like a fairly clear-cut set of relationships among related species, introducing new confusion where little existed before. Such is the case with a recent find of 1.8 million-year-old hominid fossils in the Lake Turkana basin, an area spanning across across the border between Kenya and Ethiopia.

Of course, the details of the relationships between advanced non-modern-human hominids has never been terribly simple, and has always been riddled with a certain amount of confusion and uncertainty. This new find introduces yet another piece into the puzzle. Discovered and described by the esteemed Leakey family, the new specimens include a beautifully preserved upper jawbone that may (or may not) belong to Homo rudolfensis, which is important because the holotype for this species lacks this bone. Another of the new specimens discovered by Dr. Leakey is a lower jawbone that appears to match up with the upper one. These bones are likely from the same species, but not necessarily the same individual - they seem to belong to H. rudolfensises of different ages.

So why is this situation confusing for the hominid relationship situation? Well, even though these bones mesh well together, and seem to match the holotype as well, they do not match up with another famous fossil found in the same area decades ago, which - of course - has also been assigned to H. rudolfensis all this time. This old bone, discovered in 1973, is now considered to more or less be a completely unknown species because of this new find.

It's always possible that the discrepancy can be explained by ontogeny or a degree of sexual dimorphism previously unknown in hominids, which would be very interesting to the field of human evolution for a different reason. But Dr. Leakey doesn't think so, nor does she think the old fossil was Homo habilis, which was also around at the same time and place - it looks too different. What this means is there were probably at least three different species of advanced Homo coexisting in the same time and place in Africa a little under 2 million years ago. A similar degree of diversity is well-known to have existed around 40,000 years ago, where modern humans, Neanderthals, Asian Denisovans and the Indonesian Flores "hobbits" all coexisted around the same time. Other than modern man and Neanderthals - and indeed it is now well-known that Neanderthals and modern man even interbred for a time - these four hominids would have been separated by pretty vast geographical distance. The really remarkable thing about H. habilis, H. rudolfensis and this new/old species of Homo is that they were all coexisting on the east-African savannah.

So, what's the big deal? Well, this opens up a lot of questions about human origins that are gaining more interest among anthropologists. This coexistence of at least three pre-human hominids suggests that hominids underwent intense adaptive radiation, meaning that an earlier common hominid ancestor must have differentiated in response to changing environments and food sources. This raises a host of other questions, such as: how did these extremely similar yet different hominid species differ in their food sources, habitat preferences, physical abilities, and cultures? What caused them to eventually become extinct? While there was of course never any reason to expect otherwise, it's becoming more and more clear that human evolution involved as many complexities and as much radiation as any other animal observed in the fossil record, and that our evolutionary history is far from linear.

It's difficult to come up with a "monthly question" when our article topic is merely a new discovery, but thinking about ancient hominid species coexisting with one another - both at 40,000 years ago and much earlier in Africa - made me start to wonder how modern man would react to a similar situation. I am going to go out on a limb and predict that most people's answers to this question will not be optimistic. But in any case, this month's question is: If a population of closely-related but definitely distinct species of hominid was discovered in some remote and isolated jungle, how do you think our modern society would react? How would we treat this new species, so like us yet so different? Would we afford them the same rights that we afford other members of our species, or would they be treated more like… animals?

My own answer to this question is probably more complex and more dependent on specifics that I could really go into here. First off, even if they are afforded the same rights that humans have, I don't think that they shouldn't be studied by science - humanely, of course. Discovering a living sister-group to H. sapiens would be an enormously important event, and one that could add a huge amount to our current anthropological knowledge. Aside from that, I do think that they should probably be afforded the same rights that humans have, since such a closely-related species would be very unlikely to not have a very largely overlapping range of reasoning ability, communicative faculties, and emotional depth. It's very difficult to imagine how this would play out in practice, though, and it would probably depend a lot on the specifics.  If such a small population is discovered, they would probably fit the bill for "endangered species" right from the start, and in this case "treating them like animals" could also probably include trying to bolster and protect their population in order to prevent them from going extinct. But if they were true legal and moral equals to humans, would that kind of meddling behavior be appropriate, or should they be free to make their own decisions about the fate of their populace?

The idea of discovering a new species of living Homo raises a huge number of scientific and ethical questions that humanity hasn't faced since we dwelt alongside Neanderthals in the caves of our Pleistocene past. Five hundred thousand years ago, it's difficult to think about humans and Neanderthals in a way other than the sort of competition between animals we see all the time in nature. It's very difficult to imagine how a similar situation would play out in the present.
Earlier this month, paleontologists described the newly-discovered feathered dinosaur Sciurumimus from the late Jurassic period.  Several paleoartists have already depicted this animal, including our own other admin here.  Enough feathered dinosaurs have been discovered at this point that finding yet another one might not seem to be a big deal, but Sciurumimus is unique in several ways.

First, while most of the feathered dinosaurs known at this point have been found in China, Sciurumimus was discovered in Germany.  This makes it the first nonavian dinosaur with preserved feathers discovered outside of China.  (This is not including dinosaurs where the evidence of feathers is indirect, such as the Velociraptor with quill knobs.)

Second, Sciurumimus is currently classified as a megalosaurid, although this may change in the future—it isn’t easy to tell what group of theropods it belonged to because it was so young when it died.  If it’s a megalosaurid, it is only distantly related to most of the other feathered dinosaurs discovered up to this point.  All of the other known feathered theropods are coelurosaurs, and if they share a feathered common ancestor with megalosaurids, it would mean feathers were probably an ancestral trait to all tetanuran theropods.  Tetanurans include the coelurosaurs that have been known to be feathered for several years, but they also include theropods like Spinosaurus and Allosaurus.  In other words, it would be likely that Allosaurus had a feathered ancestor, and may itself have had feathers one some part of its body, at least when it was a chick.

But the implications of Sciurumimus for how widespread feathers may have been among dinosaurs go way beyond feathered allosaurs or spinosaurs.  This is because of the third significant thing about Sciurumimus: it has what are known as “stage 1” feathers, simple hollow fibers that are the most primitive feather-like structures known to exist.  Stage 1 feathers similar to those on Sciurumimus have previously been discovered on Tianyulong, a basal ornithischian dinosaur.

Sciurumimus and Tianyulong are related to one another as distantly as it’s possible for two dinosaurs to be.  They are on opposite sides of the divide between ornithischia and saurischia, the single largest division that exists in dinosaurs.  If both Sciurumimus and Tianyulong inherited their feathers from their common ancestor, that ancestor was also the ancestor of sauropods, stegosaurs, ankylosaurs, and hadrosaurs.  It would mean that every one of these groups of dinosaur was descended from an ancestor that had feathers.

That doesn’t mean all of these dinosaurs were actually feathered—on some of them, such as the hadrosaur Edmontosaurus, skin impressions exist for the animal’s entire body showing only the scutes that dinosaurs have traditionally been depicted with.  But it would mean that feathered hadrosaurs, stegosaurs or sauropods are no longer out of the question, and also that every one of them which lacked feathers would have lost its feathers secondarily.

With that in mind, here is this month’s question: Do you think it is likely that Sciurumimus and Tianyulong inherited their feathers from their common ancestor, which was the common ancestor of all dinosaurs?  Or is it more likely that this type of feather evolved more than once?

I don’t personally have an opinion about this yet.  Sciurumimus is so recently-described that many things about it are still considered uncertain, although I’m sure that over the next few months paleontologists will be putting a lot of thought into the answer to this question.  At the moment, only one thing is certain: Sciurumimus shows that we’re still a long ways from knowing everything there is to know about dinosaurs, so new discoveries will continue bringing surprises.
Our original deadline for the recent contest was going to be today, but… we have no entries yet. So my question is, was anyone planning on entering? If so, I will consider extending the deadline.
Our last two contests were intended to celebrate benchmarks in the group - our 100-member mark and 300-member mark, respectively - but at this point it has become something of a yearly event. (Although, for anyone curious, we now have 440 members!)

The Contest: It's been said before that "a picture is worth a thousand words". One good illustration can sometimes convey a concept or argument more clearly than even the best explanation. Your task is to create a visual explanation for some aspect of evolution, or a visual refutation of a misconception about it (including creationist arguments). Optimally, we'd like the image itself to be an argument for the concept, rather than merely illustrating it. However, we will accept a broad range of submissions that fit the theme in a general sense. For example, an illustrated cladogram of a particular group of animals would be acceptable, but not a terribly creative entry.

Here are a few preexisting examples of the sort of thing we're after:
  • This comic, by Lieju, illustrates the concept of natural selection.
  • This illustration, by doctormo, illustrates the literal "evolution" of intelligent design.
  • This cartoon, by Koobine, is a humorous illustration of the absurdity of the claim that there are no transitional forms.
  • This chart, by Agahnim, is an illustrated rebuttal to the creationist designation of "kinds".
  • And this chart, also by Agahnim, shows that most creationists in the US are rejecting evolution in opposition to their church denomination's position.
  • Beautifully illustrated cladograms such as this one are also acceptable, though not preferred.

If you're not sure if an idea you have is suitable to the contest, feel free to run it by myself or Agahnim and we'll let you know.

The Rules: As is standard, works must be created specifically for the contest, and cannot be preexisting submissions.

Works must also relate in some manner to the concept of evolution. This can be from a purely biological approach, or from an anti-creationism approach. We will not accept submissions intended solely to mock religion - there must be a relevant application to evolution.

Other than that, this contest is pretty open.

The Judging: As always, the winner will be chosen by myself and the co-founder Agahnim. The winner will be chosen based on a combination of skill, style, and creativity. Though a wide range of possibilities exist for this contest, preference will be given to those illustrating a particularly clever, complex, elegant and well-executed evolutionary or anti-creationist concept. Please be creative! This contest should be a chance not just to show off your artwork and win a prize, but to also educate our viewers.

The deadline for all entries will be July 1st.

The Prize: And of course, the best part of any contest. We will select ONE entrant who will win a SIGNED, first-edition copy of Unweaving the Rainbow by Richard Dawkins. Photographs of the signature can be provided upon request if there are any doubters. This is a once in a lifetime prize opportunity! However, there is one caveat: this prize will only be available if five or more people enter the contest. If we get fewer than five entrants, the prize will be a year-long DA subscription.

As with last year, you must be comfortable giving your mailing address to me in order to receive the prize. In the event that our winner is not comfortable with that, we can substitute the prize for a year's DA subscription, if you really want to be that boring. (I agree to keep your address and so on completely private, no worries.)

Good luck and have fun!
I was originally intending for this month’s featured topic to be about Yutyrannus, a one-ton feathered tyrannosaur that’s the largest dinosaur (or animal of any sort) to be found with feathers.  But as interesting as Yutyrannus is, this month has also had another piece of dinosaur-related news that’s a little more unusual—although the way in which it involves dinosaurs is pretty far-fetched.

This paper published in the Journal of the American Chemical Society discusses the concept of chirality, which is the way it’s possible for a molecule with a particular structure to exist in two different “versions”, one of which is a mirror image of the other.  The paper suggests that the reason why amino acids on earth tend to have a particular chirality might be because amino acids with that chirality were delivered to prehistoric earth on meteorites.  For the most part it’s a fairly standard biochemistry paper, but it concludes in a unique way:
An 
implication 
from
 this 
work 
is 
that 
elsewhere 
in 
the 
universe 
there 
could 
be 
life 
forms 
based
 on 
D 
amino 
acids 
and 
L 
sugars, 
depending 
on 
the 
chirality 
of 
circular 
polarized
 light 
in
 that 
sector 
of 
the universe or 
whatever 
other 
process 
operated 
to 
favor 
the 
L
α‐methyl 
amino acids 
in 
the 
meteorites 
that 
have landed
 on Earth. 

Such 
life 
forms 
could 
well 
be 
advanced 
versions 
of 
dinosaurs, 
if 
mammals 
did 
not 
have the good
 fortune 
to 
have 
the 
dinosaurs 
wiped 
out 
by 
an 
asteroidal 
collision,
 as 
on 
Earth. 

We 
would 
be 
better 
off not 
meeting 
them.

Dinosaurs are not mentioned anywhere in the paper besides the closing paragraph, so bringing them up in the last paragraph isn’t exactly well-supported in a scientific sense.  This doesn’t have to be a problem, though.  As long as other scientists understand that this was just meant to be funny, it doesn’t do any harm for a scientific paper to include something fanciful for the sake of humor… at least not until the media catch hold of it.

Here is Google’s list of news stories about this paper.  There are too many to list, but the titles should make it obvious what aspect of the paper they’re exclusively focusing on.  The article at Science Daily is titled “Could 'Advanced' Dinosaurs Rule Other Planets?”, while the article at The Register is titled “Death Star dinosaur aliens could rule galaxy”.  The first sentence of the Register article is one of the best examples of what the media has to say about this paper which was discussing molecular chirality: “Rather than dying out in the dimly lit aftermath of a ginormous asteroid impact, dinosaurs on Earth may have instead spread to other planets and built a terrifying space-conquering empire.”

Of course, the real question is whether the paper’s author, Ronald Breslow, should be blamed for any of this.  In the past I’ve tended to assume situations like this are the fault of the media alone, but there have also been a few situations like this one where scientists have clearly manipulated the media coverage of their papers in order to get as much positive press as possible.  The article’s press release, which appears to be no longer online, clearly emphasized the “space dinosaurs” idea over the actual content of the paper—it’s anyone’s guess whether that was the original author’s idea or not.

In any case, during the weeks since the paper was accepted for publication, there’s been a second problem.  As pointed out here, it was eventually discovered that a large portion of the paper had been copied word-for-word from previous papers that the author had published in other journals.  The same post also points out how surprising this is, when one considers the author’s credentials:  he’s a member of the National Academy of Sciences, the former president of the American Chemical Society, and has won numerous awards.  Plagiarizing one’s own writing isn’t as bad as plagiarizing someone else’s, but what he’s done is attempt to publish essentially the same paper in multiple journals under different titles, which goes against the American Chemical Society’s code of ethics.

Due to the self-plagiarism issue, the paper has now been removed from the website of the journal that published it.  With the original paper vanished, the news media coverage is now all that’s left.  In other words, anyone reading these news articles about space dinosaurs will no longer have any way to look up the original paper and see what it’s actually about.

We’ve had many previous posts about the errors and excesses of science journalism, but in my opinion this particular instance is one of the worst examples I’ve ever encountered.  So here is this month’s question: What should be done to prevent the science media from misrepresenting research in this manner?

In the past, I’ve suggested that one of the solutions is for scientists to write at least some of the news stories about their own research.  However, that doesn’t solve the problem of situations where scientists are deliberately trying to manipulate public perception of their research, as in the case of the arsenic bacteria paper.  In situations like that, scientists writing the popular accounts of their research would not make the problem any better.

Perhaps another solution would be news sources to require science journalists to meet a minimum requirement of training about science.  Most colleges and universities expect that in order for someone to be qualified as a professor, they should have either a master’s degree or a Ph.D in the subject they’re teaching.  Science journalists play just as important a role in informing the public about science as professors do, but the only requirement for someone to be a science journalist is that they be trained in journalism.  Perhaps someday, this double standard can be fixed.

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