NGM Blog Central - Darwinius and the Real Missing Link - National Geographic Magazine

Eosimias.lr Why was Eosimias, shown here, left out of a scientific discussion about the origins of monkeys, apes, and humans and the recent announcement of Darwinius? The answer depends on who you ask. Model by Brian Cooley. Photograph by author.

Behind the over-hyped quotes about a “missing link” (which I thought we all learned does not exist in nature) is an intriguing story about a longstanding scientific debate. The argument concerns what group anthropoids (monkeys, apes, and humans) evolved from. Yesterday, scientists presented Darwinius masillae, a superbly preserved fossil from the world famous Messel fossil site in Germany, as evidence to support the idea that anthropoids could have evolved from adapoids, a group of arboreal quadrupeds that lived over 55 million years ago. Proponents of this idea include two giants in the study of early mammals, Elywn Simons of Duke University and Philip Gingerich of the University of Michigan (an author on the paper published in PLoS One), among others. Both Simons and Gingerich are grantees of the National Geographic Society. On the other side of the debate are scientists who see evidence that the adapoids were the ancestors of lemurs and lorises, not anthropoids. Instead, they argue that the ancestor of anthropoids evolved from the omomyoids, another group of arboreal quadrupeds that lived at the same time as the adapoids during the Paleocene and Eocene epochs (66 to 35 million years ago).

Darwinius is not going to end this debate. One of the main points the authors of the PLoS One paper want to make, however, is that now there is a benchmark for what good early primate fossil material looks like. In an e-mail earlier today, Gingerich wrote “Darwinius raises the bar for completeness and interpretation of an Eocene primate by associating many anatomical/morphological characteristics unequivocally in one skeleton.” Indeed, because of the completeness of the fossil, which included a body outline and a fossilized digestive tract, the authors were able to delve into an area not often seen in such detail in paleontology papers—the biology of an extinct animal. The discussion included body size, diet, locomotion, and growth and development.

Gingerich hopes that well-preserved fossils like Darwinius will be compared to what he calls “cladistic anthropoids.” These are fragmentary fossils with enough features, called characters, to place them taxonomically within the anthropoid group, Anthropoidea, in a cladistic analysis. But not all scientists agree with the cladistic approach. Gingerich is one. Gingerich and the other authors of the Darwinius paper state that “the history of Anthropoidea is traced through the Eocene in somewhat speculatively identified lineages of isolated teeth.” By comparing Darwinius to such “cladistic anthropoids,” Gingerich hopes to set lights on which characters matter in the evolution of anthropoids and which may not.

An artist's reconstruction of the ecosystem at the Messel fossil site in Germany during the Eocene, based on fossils collected there. In the upper left corner is an adapoid primate, Europolemur, a close relative of Darwinius. Art by Christopher Klein and Mark Hallett.
Messel_lr

Chris Beard of the Carnegie Museum of Natural History is outraged with the paper and the media hype surrounding it. He is a leading proponent of the hypothesis that anthropoids evolved from a common ancestor they shared with the omomyoids, not the adapoids. He is also the scientist who described Eosimias, a strong candidate for the ancestor of the earliest known anthropoids. The fragmentary Eosimias fossil was discovered in China in 1994. “Isn’t it strange that they don’t even mention Eosimias in their paper?,” Beard asked in an e-mail earlier today. “It is dishonest to describe a fossil that purports to tell us something about anthropoid origins without at least comparing it to Eosimias, which is the single most important fossil currently known that bears on anthropoid origins.”

Beard is not alone in expressing disappointment with the roll out of Darwinius. In a FoxNews.com article entitled “Scientists: 'Missing Link' Fossil Not Worth Media Hype” by Clara Moskowitz, primate fossil experts John Fleagle of Stony Brook University and Richard Kay of Duke University appear underwhelmed. In that article, Kay criticizes the paper, saying “they failed to cite a body of literature that's been going on since at least 1984 that presents evidence against their hypothesis." Kay goes on to mention that he missed a comparison to the eosimiads. For the record, the authors of the Darwinius paper referred to recent evidence of early anthropoids from Asia in a note.

Fortunately, there will be plenty of time to make the comparisons that Gingerich, Beard, and Kay all want to see. The Darwinius fossil is finally out of the private hands of a collector, where it has remained hidden from science since the early 1980s. Now the specimen can be studied at its new home in a museum in Oslo, Norway.

For Gingerich, who began studying the fossil two years ago, there is great importance in what this amazing new fossil can tell us. For others, something was lacking in the fossil’s debut. Maybe there is a missing link after all. Could it be what the science paper and the press releases didn’t say?

The Darwinius fossil on the left was in a private collection for 27 years. The fossil on the right is the counterpart, but contains large areas (outside dashed lines) that were faked. PLoS One/Creative Commons
Fossil

I’d be interested in your comments on any of this, but particularly on:
—Missing links
—The fossil publicity blitz
—Where the fossil has been for 27 years and is that right?
—How to pronounce “Omomyoids”

Posted by Chris Sloan | Comments (11)
Filed Under: Stones, Bones ‘n Things

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Lette
May 21, 2009 12AM #

well were not the 2 fragments found and somehow seperated back in 1983 I think I read and they have only been reunited recently and inturn could not be properly examined untill now?

Bob Hardy
May 21, 2009 12AM #

The news I have seen on Darwinius so far has a missing link. That is the reporting doesn't link Darwinius to humans.

We should not have ever heard the term "Missing Link" if there was any truth to darwinian evolution. If evolution was in any way true we would see multiple millions of links proving all, or most, of the supposed species transitions.

The science leads one (including thousands of credentialed scientists) to the concept of Biblical creation.

Pete
May 21, 2009 12AM #

"Biblical creation?" It's even hard to say those words but how challenging is this concept! I have seen all these so called 'evidences of evolution' (particularly whale evolution) and time and time again i am left feeling somewhat conned! According to Attenborough the link "is no longer missing" well I'm sorry but i think the only thing that's missing here is honesty!

hi tony
May 21, 2009 12AM #

The fossil on the right is missing it's hands and feet, so those must have been reconstructed.

Holly
May 21, 2009 12AM #

The connection to humans isnt a direct ancestor on our "branch", if I understand correctly the Darwinius fossil is proposed as a species at the point of speciation where the two groups will evolve further to become the lemuer etc group or the "human" etc group.

Of course you could consider many species as links from one species to another more evolved one but it is easier to see when you have two clearly distinct species (humans and lemurs) and something recognisable as an intermediate, the evoloution happens in many tiny steps so to the untrained eye the differences wouldnt be notieable enough to create this sort of media attention.(which whilst slightly misleading in its labeling, because "the missing link" indicates some sort of hominoid species, is still a worthwhile news story)

Regarding the lack of link species, the conditions for fossilisation are highly specific and even then you're looking at "hard parts" eg bones, that's why this is such a brilliant find because the are other preserved features. Aside from that evidence is constrained to fossils any more there certainly are multiple cases of DNA and Protein similarities reflecting evolutionary relationships.

I'd be interested in knowing which part of the theory it is that leaves people feeling conned, or is it rather the lack of fossil evidence?

Warren Dew
May 21, 2009 12AM #

I'm guessing the reason these guys didn't mention eosimias was because they figured their data was much stronger, given the completeness of the darwinias fossil. The "outrage" in the opposing camp sounds like people who are trying to hold on to what they are used to rather than examining new data objectively.

David
May 21, 2009 12AM #

According to this site: http://www.icr.org/article/4642/ there are many scientists, evolutionists and creationists, that are underwhelmed as well. I'm particularly interested in the teeth formation and the fact that this fossil was found in "newer" layers than layers in which fossils of monkeys have been found.

Davf
May 21, 2009 12AM #

I've always been intrigued by the "many tiny steps" that to the "untrained eye" cannot be recognized while holding to the "compare two distinct species and find the commonality" idea. Herein lies the real missing link; the connection between what is real (two distinct species) and what is imagined (all the tiny steps). This seems to be the mode of operation for all evolutionary study. Like the "artists rendition" of the Messel pit above. What continues to be the "proof of concept" for evolution is the skill of the artist. Sadly, the scientific industry has borrowed from the mechanical industry; the designers (artists) create the concept and the engineers (scientists) try to build it. The only difference is that the scientists tell the artists what the model is to look like while they search for the bones to create the concept model.

Kelsey
May 21, 2009 12AM #

I am not very knowledgeable on this subject, but is it not possible that humans may have evolved in different regions in different ways?

4Anthro
May 21, 2009 12AM #

Ida was not "reconstructed" and her hands and feet are not missing from the picture. Ida died drowning in the Messel Pit waters. The Oslo team figured this out because she had a broken wrist that had begun to heal (forming a giant knot). Clearly the arboreal Ida was forced from the trees down the the ground to search for water.
As for those anti-evolutionists, your ignorance on the subject is astounding. You have certain beliefs and are unwilling to look at this subject and see it for what it really is. Ida is a 47 million year old fossil that has been perfectly preserved. That, in and of itself, is a great feat. You say that the media doesn't try to directly relate it to humans, but if you actually looked and read the book, or watched the film, or even went to the reavealing the link website, you would see that it goes in to specific detail about how Ida is connected to the anthropoid line. She is also related to the the prosimian line. She is neither and both. This is why she has been labled the "Missing Link". She is not the only missing link. There are still many that need to be found. What you don't realize is how unbelievably hard it is for a fossil to be formed and survive that long. You ask why there aren't hundreds more of these fossils floating around. The answer is that it is only under special conditions and remarkable circumstances that a fossil is able to be formed. Not all places in the world have the right conditions for preserving a fossil.
Most places don't. And, not all animals are all over in every part of the world. Some are only in certain regions, and if these regions are not able to support the formation of a fossil, then there is no way for these creatures to be preserved for the next million years.
If you would only take a step back and look at it without bias, you would be able to appreciate what a truly remarkable find that this is. And if you are too close-minded to see this, then you should ignore the subject and let the scientists study what they would like, without all of this arguing and disagreeing.

DARREL
May 21, 2009 12AM #

And should we let the same "scientists" who revealed Piltdown to us do ALL the investigating in this arena? I understand that there was no arguing and disagreeing then.

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