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Old May19-09, 11:23 PM                  #1
gravenewworld

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Missing link found?

http://news.nationalgeographic.com/n...ssil-link.html


Any evolutionary biologists here? What do you think?
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Old May19-09, 11:25 PM                  #2
DaveC426913
 
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Re: Missing link found?

Yeah. This is awesome.

But. I hedge my bets. Throw a few bucks on "hoax" and on "viral movie promo".
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Old May20-09, 07:20 AM                  #3
Moridin

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Re: Missing link found?

This has probably been said many times before on this forum, but "missing link" is an invalid concept in evolutionary biology since evolution is not the great chain of being, but a tree of life. What they have claimed to found is thus a potential common ancestor to both humans and lemurs with human/lemur diagnostic features.
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Old May20-09, 08:44 AM                  #4
Andy Resnick

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Re: Missing link found?

Here's the just-released paper:

http://www.plosone.org/article/info:...l.pone.0005723
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Old May20-09, 02:37 PM                  #5
BoomBoom

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Re: Missing link found?

Very cool!

It is somewhat odd that such a find was actually made in 1983 and remained unknown until being turned over to a museum more than 25 years later. I wonder how many other great finds made by amateurs are just sitting out there "undiscovered" on someones mantle or in a closet or something?
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Old May20-09, 03:22 PM                  #6
Monique

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Re: Missing link found?

The conclusion of the paper:
Originally Posted by Plos One
We can now document the history of an extraordinary fossil, here named Darwinius masillae. Its two parts, although split by private collectors and dispersed to two continents, are virtually reunited here 26 years after discovery. The fossil, including an entire soft body outline (preserved in the Oslo specimen) as well as contents of the digestive tract (investigated in the Wyoming specimen), documents paleobiology and morphology of an extinct early primate from the Eocene of Germany.

After comparative study, we conclude that the Darwinius holotype was a juvenile female, weaned and feeding independently on fruit and leaves in the middle floor of early Middle Eocene rain forest of Messel. She may have been nocturnal. She moved as an agile, nail bearing arboreal quadruped and, although perhaps only 60 percent of adult weight at death (Fig. 12), would have grown to be the size of an adult female Hapalemur, in the range of 650–900 g. Her pattern of tooth development shows that her species grew up fairly quickly and suggests that she died before one year of age.

Darwinius masillae is now the third primate species from the Messel locality that belongs to the cercamoniine adapiforms, in addition to Europolemur koenigswaldi and E. kelleri. Darwinius masillae is unrelated to Godinotia neglecta from Geiseltal, which was much more slenderly built. Darwinius and Godinotia neglecta are similar, however, in the degree of reduction of their antemolar dentition. Morphological characteristics preserved in Darwinius masillae enable a rigorous comparison with the two principal subdivisions of living primates: Strepsirrhini and Haplorhini. Defining characters of Darwinius ally it with early haplorhines rather than strepsirrhines. We do not interpret Darwinius as anthropoid, but the adapoid primates it represents deserve more careful comparison with higher primates than they have received in the past.

Darwinius masillae is important in being exceptionally well preserved and providing a much more complete understanding of the paleobiology of an Eocene primate than was available in the past.

Link to the publication
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Old May20-09, 05:00 PM       Last edited by Orion1; May20-09 at 06:42 PM..            #7
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Cool Darwinius masillae...


paleontologist Jorn Hurum, who led the team that analyzed the 47-million-year-old fossil, suggests Ida is a critical missing-link species in primate evolution

The fossil, he says, bridges the evolutionary split between higher primates such as monkeys, apes, and humans and their more distant relatives such as lemurs.

Ida, properly known as Darwinius masillae, has a unique anatomy. The lemur-like skeleton features primate-like characteristics, including grasping hands, opposable thumbs, clawless digits with nails, and relatively short limbs.

At least one aspect of Ida is unquestionably unique: her incredible preservation, unheard of in specimens from the Eocene era, when early primates underwent a period of rapid evolution.

In Ida's case, scientists were able to examine fossil evidence of fur and soft tissue and even picked through the remains of her last meal: fruits, seeds, and leaves.

What's more, the newly described "missing link" was found in Germany's Messel Pit. Ida's European origins are intriguing, Richmond said, because they could suggest—contrary to common assumptions—that the continent was an important area for primate evolution.

47 million years ago, Ida's rainforest was located on the same latitude as the southern coast of present day Spain. Floral and faunal fossils indicate that Ida lived in a warm, humid rainforest that teemed with life. Over 300 species of plants and animals have been identified - but these represent only a fraction of the life that existed here as much of the plant life would have quickly rotted in the moist jungle heat.

Reference:
National Geographic - missing link found
Revealing the Link - discovery
Revealing the Link - uncovering Ida
Revealing the Link - rainforest
Attached Images
File Type: jpg 090519-missing-link-found_big.jpg (124.0 KB, 4 views)
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Old May21-09, 02:47 AM                  #8
MATLABdude

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Re: Missing link found?

Originally Posted by gravenewworld View Post
http://news.nationalgeographic.com/n...ssil-link.html


Any evolutionary biologists here? What do you think?
In regards to filling in the gaps in the evolutionary record, I remember reading this quote somewhere, someplace:

Originally Posted by Unknown
Where there was only one gap in the evolutionary record for creationists to complain about, now there are two.
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Old May21-09, 10:22 AM       Last edited by sylas; May21-09 at 02:36 PM.. Reason: postscript            #9
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Re: Missing link found?

Originally Posted by Moridin View Post
"... a potential common ancestor to both humans and lemurs ..."
While this is true enough, it has very limited meaning. We don't find "common ancestors"; and there's no way to tell if you have a "common ancestor". What you may have is a species which is close to the line of ancestry, but you can never actually tell if a particular fossil represents a species that became extinct (the most usual case!) or a species that went on to to be ancestral to other species now living.

PS. Note that I am not presenting this ias skepticism about the find, but about the nature of fossils and the general form of scientific inferences from fossils. I'm emphasizing "cladistic" reasoning. Finds like this this are exciting and tell us lots about the nature of our evolutionary history, and hence about our ancestry. Meanginful falsifiable conclusions and hypotheses about fossil are about whether it is more or less closely related: not about whether it is directly ancestral or not. Being "directly" ancestral is an amusing speeculation. The real information being obtained, however, is a phylogeny. The questions are never -- is this ancestral to that, but is this more closely related to that than to something else?

In other words, the scientific inference is not about ancetry relationships between fossils, or species, but inferences about which fossils have the most recent common ancestors. It's a subtle difference, but worth understanding.
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Old May21-09, 12:40 PM                  #10
jamesb-uk

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Re: Missing link found?

I don't think we should leap to conclusions about the nature of this find. The paper they sent out doesn't mention any kind of 'missing link', and is very cautious in how it is written regarding this concept. The paper hasn't even been fully peer reviewed yet, so we should not assume it is good enough to base these speculations on. I think that although this is an amazing find because of the age and the nature of it, the idea that it is one of our direct ancestors has been 'hyped up' by the media, like many science stories.
I'm not saying it is definitely not our ancestor, but that we can not be certain.
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Old May21-09, 03:23 PM                  #11
BoomBoom

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Re: Missing link found?

Originally Posted by jamesb-uk View Post
I don't think we should leap to conclusions about the nature of this find. The paper they sent out doesn't mention any kind of 'missing link', and is very cautious in how it is written regarding this concept.
Well any new fossil find that uncovers a previously unknown species (especially from the era from which this specimen came from where there is so little data), is very valuable regardless of whether or not it is a "direct" descedent.

As Moridin pointed out, it's not so much a "missing link" as it is a "missing branch" of the tree of life. And this one in particular that seems to be near the beginning of the emergence of primates is a great piece to add to the puzzle! (assuming no hoaxes, of course)
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Old May21-09, 05:20 PM                  #12
arildno

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Re: Missing link found?

Mr. Jørn Hurum, who is a somewhat flamboyant Norwegian paleontologist (if that is possible!), is also a shrewd media manipulator.

He knows that the find and the two years of research prior to publication (!) stands very well on its own, scientifically speaking.
It is a tremendously important find, mainly due to its extremely good state of preservation (rather than being some sort of critical link).

However, Mr. Hurum wants more:
Namely to whip up non-paleontological enthusiasm for Ida (incidentally named after his own 6-year old daughter..), and to get the media going, he uses the "missing link" metaphor, since "missing links" sounds so mysterious and exciting...
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Old May21-09, 05:44 PM                  #13
jamesb-uk

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Re: Missing link found?

Originally Posted by BoomBoom View Post
Well any new fossil find that uncovers a previously unknown species (especially from the era from which this specimen came from where there is so little data), is very valuable regardless of whether or not it is a "direct" descedent.

As Moridin pointed out, it's not so much a "missing link" as it is a "missing branch" of the tree of life. And this one in particular that seems to be near the beginning of the emergence of primates is a great piece to add to the puzzle! (assuming no hoaxes, of course)
Absolutely, I wasn't saying it was worthless, I was just saying we don't know for certain what it is. I think it's an amazing find, because of how old and well preserved it is, and because of the particular species.
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Old May21-09, 11:28 PM                  #14
Moridin

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Re: Missing link found?

Originally Posted by MATLABdude View Post
In regards to filling in the gaps in the evolutionary record, I remember reading this quote somewhere, someplace:
Standard part of Duane Gish's talks.
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Old May23-09, 09:02 PM                  #15
kasse

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Re: Missing link found?

My creationist friend says this has just strengthened his faith, because now there are TWO missing links - one before and one after Ida.
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Old May23-09, 09:46 PM                  #16
Proton Soup

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Re: Missing link found?

"missing link" is nothing more than PT Barnum speak. in the interest of science, they paid $1,000,000 USD for a fossil, and now they're hyping the crap out of it to try and recover their investment. yay science!
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