Author Topic: Fossil Review Confirms Co-existence of Hominin Species  (Read 1018 times)

Offline stromboli (OP)

Fossil Review Confirms Co-existence of Hominin Species
« on: June 08, 2016, 04:40:39 AM »
https://www.cmnh.org/announcements/pnas-lucy

LUCY HAD NEIGHBORS
Posted: June 06, 2016

Quote
If “Lucy” wasn’t alone, who else was in her neighborhood? Key fossil discoveries over the last few decades in Africa indicate that multiple early human ancestor species lived at the same time more than 3 million years ago. A new review of fossil evidence from the last few decades examines four identified hominin species that co-existed between 3.8 and 3.3 million years ago during the middle Pliocene. A team of scientists compiled an overview that outlines a diverse evolutionary past and raises new questions about how ancient species shared the landscape. The perspective paper, “The Pliocene hominin diversity conundrum: Do more fossils mean less clarity?” published June 6 as part of a Human Origins Special Feature in the Early Edition of the Proceedings of the National Academy of Sciences.

Authors Dr. Yohannes Haile-Selassie and Dr. Denise Su of The Cleveland Museum of Natural History and Dr. Stephanie Melillo of the Max Planck Institute for Evolutionary Anthropology in Germany provide an up-to-date review of middle Pliocene hominin fossils found in Ethiopia, Kenya and Chad. The researchers trace the fossil record, which illustrates a timeline placing multiple species overlapping in time and geographic space. Their insights spur further questions about how these early human ancestors were related and shared resources.

“It is now obvious that more than one species of early hominin co-existed during Lucy’s time,” said lead author Dr. Yohannes Haile-Selassie, curator of physical anthropology at The Cleveland Museum of Natural History. “The question now is not whether Australopithecus afarensis, the species to which the famous Lucy belongs, was the only potential human ancestor species that roamed in what is now the Afar region of Ethiopia during the middle Pliocene, but how these species are related to each other and exploited available resources.”

The 1974 discovery of Australopithecus afarensis, which lived from 3.8 to 2.9 million years ago, was a major milestone in paleoanthropology that pushed the record of hominins earlier than 3 million years ago and demonstrated the antiquity of human-like walking. Scientists have long argued that there was only one pre-human species at any given time before 3 million years ago that gave rise to another new species through time in a linear manner. This was what the fossil record appeared to indicate until the end of the 20th century. The discovery of Australopithecus bahrelghazali from Chad in 1995 and Kenyanthropus platyops from Kenya in 2001 challenged this idea. However, these two species were not widely accepted, rather considered as geographic variants of Lucy’s species, Australopithecus afarensis. The discovery of the 3.4 million-year-old Burtele partial foot from the Woranso-Mille announced by Haile-Selassie in 2012 was the first conclusive evidence that another early human ancestor species lived alongside Australopithecus afarensis. In 2015, fossils recovered from Haile-Selassie’s ongoing research site at the Woranso-Mille area of the Afar region of Ethiopia were assigned to the new species Australopithecus deyiremeda. However, the Burtele partial foot was not included in this species.

“The Woranso-Mille paleontological study area in Ethiopia’s Afar region reveals that there were at least two, if not three, early human species living at the same time and in close geographic proximity,” said Haile-Selassie. “This key research site has yielded new and unexpected evidence indicating that there were multiple species with different locomotor and dietary adaptations. For nearly four decades, Australopithecus afarensis was the only known species—but recent discoveries are opening a new window into our evolutionary past.”

Co-author Dr. Denise Su, curator of paleobotany and paleoecology at The Cleveland Museum of Natural History, reconstructs ancient ecosystems. “These new fossil discoveries from Woranso-Mille are bringing forth avenues of research that we have not considered before,” said Su. “How did multiple closely related species manage to co-exist in a relatively small area? How did they partition the available resources? These new discoveries keep expanding our knowledge and, at the same time, raise more questions about human origins.”

Paleoanthropologists face the challenges and debates that arise from small sample sizes, poorly preserved prehistoric specimens and lack of evidence for ecological diversity. Questions remain about the relationships of middle Pliocene hominins and what adaptive strategies might have allowed for the coexistence of multiple, closely related species.

“We continue to search for more fossils,” said Dr. Stephanie Melillo of the Max Planck Institute for Evolutionary Anthropology in Germany. “We know a lot about the skeleton of A. afarensis, but for the other middle Pliocene species, most of the anatomy remains unknown. Ultimately, larger sample sizes will be the key to sorting out which species are present and how they are related. This makes every fossil discovery all the more exciting.”

There is sufficient evidence that Neanderthal man has been incorporated into Homo Sapiens. But this is much later on the time scale, like 100,000 to 30,000 years ago. Nature has never been anything but diverse, as Darwin demonstrated in the Galapagos with finches and has been demonstrated elsewhere. Look at the number of different monkey species worldwide; you have 2 suborders and 2 families just in apes. A total number of species in a given area of just monkeys can run into the dozens.

It would appear the from an evolution standpoint nature likes to shoot out several variations on a theme and then let the more capable species survive, leaving less in number but better adapted. There are now only us and the great apes. Gorillas and Orang Utans are both threatened species. So we have us, Chimpanzees and Bonobos.

Sample size and limited fossil finds are the big problems for obvious reasons. But what interests me is that these all seem to be in a relatively small area geographically, which means something drove an evolutionary effort to create a hominid or hominid like primate. All the features of a Hominid, upright walking on two legs, emphasis on vision over other senses, apparently proved to be sufficiently useful to create a diverse effort to pass it on. Past indications are that climate change has been a factor. Interesting to see how this develops. With global warming we might all eventually be turned into camels.
« Last Edit: June 08, 2016, 04:53:31 AM by stromboli »

Re: Fossil Review Confirms Co-existence of Hominin Species
« Reply #1 on: June 08, 2016, 07:06:24 AM »
How fucking cool is that! *Awe.

Offline SGOS

Re: Fossil Review Confirms Co-existence of Hominin Species
« Reply #2 on: June 08, 2016, 07:42:45 AM »
A number of books I've read lately about hominids point to a lot of concurrent hominid species coexisting throughout our past.  I almost get the impression that "man the one," as we know him today, is an exception to the rule.  So much has changed about anthropology since I was in college because of new fossil finds that were still undiscovered just 50 years ago.

Offline stromboli (OP)

Re: Fossil Review Confirms Co-existence of Hominin Species
« Reply #3 on: June 08, 2016, 09:54:52 AM »
A number of books I've read lately about hominids point to a lot of concurrent hominid species coexisting throughout our past.  I almost get the impression that "man the one," as we know him today, is an exception to the rule.  So much has changed about anthropology since I was in college because of new fossil finds that were still undiscovered just 50 years ago.

As I understand evolution, it makes sense. In a time of plenty expand and flourish and encourage different aspects of several similar species, then in a time of want those with specific adaptations survive and the others die off. Ironically that is happening to the Orang Utans because of human deforestation to grow Palm oil trees. We are wiping out potential competitors for cosmetic companies.

Re: Fossil Review Confirms Co-existence of Hominin Species
« Reply #4 on: June 08, 2016, 11:54:57 AM »
https://www.cmnh.org/announcements/pnas-lucy

LUCY HAD NEIGHBORS
Posted: June 06, 2016

There is sufficient evidence that Neanderthal man has been incorporated into Homo Sapiens. But this is much later on the time scale, like 100,000 to 30,000 years ago. Nature has never been anything but diverse, as Darwin demonstrated in the Galapagos with finches and has been demonstrated elsewhere. Look at the number of different monkey species worldwide; you have 2 suborders and 2 families just in apes. A total number of species in a given area of just monkeys can run into the dozens.

It would appear the from an evolution standpoint nature likes to shoot out several variations on a theme and then let the more capable species survive, leaving less in number but better adapted. There are now only us and the great apes. Gorillas and Orang Utans are both threatened species. So we have us, Chimpanzees and Bonobos.

Sample size and limited fossil finds are the big problems for obvious reasons. But what interests me is that these all seem to be in a relatively small area geographically, which means something drove an evolutionary effort to create a hominid or hominid like primate. All the features of a Hominid, upright walking on two legs, emphasis on vision over other senses, apparently proved to be sufficiently useful to create a diverse effort to pass it on. Past indications are that climate change has been a factor. Interesting to see how this develops. With global warming we might all eventually be turned into camels.

Aaahhhhh!!!!!   You are a subversive!   Trying to trick us with a subtle pitch for "intelligent design" eh?    Igor!!!  Warm up the tongs!   

Just pickin' on you!  .)

Offline stromboli (OP)

Re: Fossil Review Confirms Co-existence of Hominin Species
« Reply #5 on: June 08, 2016, 12:26:04 PM »
Lol. Species thrive and survive based on availability of food and water in their specific environment. In times of plenty they thrive; which causes over population and an abundance for predators, as well as a detriment to the species. Also loss of food and water resources is counterproductive to the species. It all balances out over time. the hardy members of the species survive, and pass on their genes to the next generation.

But we are different. Because we can create food sources specific to our needs artificially-as opposed to natural production of resources- and bring water into arid regions, again artificially. But- and a big but- is that we are still subject to climactic changes such as global warming or depletion of aquifers. That is what is happening now in Syria and elsewhere in the Middle East. Loss of water and resources because of war and climate change and depletion of aquifers. And heat sufficient to overwhelm the means to combat it. Asphalt roads in India are melting in the rising daytime heat.

We change the natural balance that allows for populations thriving outside of their normal resource/water availability. Unfortunately that also allows for members of the species that are less than fully viable to exist and even pass on their genes. Given a strictly governed population control based on resource availability, that could be controlled.

But in countries that are either theocracies or have strongly hierarchical governments and a significant population of impoverished citizens, the result is what we are seeing now- mass migration to other countries that still have resources. but that won't work over the long term. You can only allocate so many finite resources to so many people. As conditions worsen- and they will- you are going to reach a point where absorbing refugees no longer makes sense.

And the result will be chaos. Reefs dying, ocean resources disappearing-80% of the population lives in coastal habitats- and loss of water for crops inland  and a host of related problems- invasive species, trees dying from longer periods of warming and so on. Doesn't paint a pretty picture.

« Last Edit: June 08, 2016, 12:29:16 PM by stromboli »

Online Baruch

Re: Fossil Review Confirms Co-existence of Hominin Species
« Reply #6 on: June 08, 2016, 01:17:34 PM »
What I have seen/read recently, the move from a forest environment to a savannah environment in E Africa, forced the bonobo like species to learn to walk and eventually run ... to avoid the leopards ... who were also sharing those trees.  So we had to move out of the trees as well, to rock shelters.
שלום

Offline stromboli (OP)

Re: Fossil Review Confirms Co-existence of Hominin Species
« Reply #7 on: June 08, 2016, 01:43:57 PM »
What I have seen/read recently, the move from a forest environment to a savannah environment in E Africa, forced the bonobo like species to learn to walk and eventually run ... to avoid the leopards ... who were also sharing those trees.  So we had to move out of the trees as well, to rock shelters.

Certainly, but what caused that move is what might be driving our situation today. Thre have been plenty of climate shifts historically and prehistorically.

Btw, Baruch, I'm thinking of having a T-shirt made. Says "NATURALIST" and beneath it "I worship the earth I walk on." What do you think?  :biggrin:

Online Baruch

Re: Fossil Review Confirms Co-existence of Hominin Species
« Reply #8 on: June 08, 2016, 06:36:05 PM »
Certainly, but what caused that move is what might be driving our situation today. Thre have been plenty of climate shifts historically and prehistorically.

Btw, Baruch, I'm thinking of having a T-shirt made. Says "NATURALIST" and beneath it "I worship the earth I walk on." What do you think?  :biggrin:

Sounds reasonable.  In my case, probably a t-shirt with a head of Bacchus, and "I worship the grapes I stomp on." ;-)
שלום

Offline stromboli (OP)

Re: Fossil Review Confirms Co-existence of Hominin Species
« Reply #9 on: June 08, 2016, 10:27:27 PM »
Sounds reasonable.  In my case, probably a t-shirt with a head of Bacchus, and "I worship the grapes I stomp on." ;-)

Sounds tasteful.

Re: Fossil Review Confirms Co-existence of Hominin Species
« Reply #10 on: June 09, 2016, 10:16:29 AM »
Lee Berger was saying this last year.
We 'new atheists' have a reputation for being militant, but make no mistake  we didn't start this war. If you want to place blame put it on the the religious zealots who have been poisoning the minds of the  young for a long long time."
PZ Myers

Offline stromboli (OP)

Re: Fossil Review Confirms Co-existence of Hominin Species
« Reply #11 on: June 09, 2016, 01:43:35 PM »
Lee Berger was saying this last year.

Yes. This is reconfirmation. There was another link I didn't include, should have.

Re: Fossil Review Confirms Co-existence of Hominin Species
« Reply #12 on: June 10, 2016, 05:55:06 AM »
Yes. This is reconfirmation. There was another link I didn't include, should have.
Cool then. Have you seen "Dawn of Humanity" (PBS)?
We 'new atheists' have a reputation for being militant, but make no mistake  we didn't start this war. If you want to place blame put it on the the religious zealots who have been poisoning the minds of the  young for a long long time."
PZ Myers

Offline stromboli (OP)

Re: Fossil Review Confirms Co-existence of Hominin Species
« Reply #13 on: June 10, 2016, 11:28:39 AM »
Cool then. Have you seen "Dawn of Humanity" (PBS)?

No, but I will when the time presents itself.

Re: Fossil Review Confirms Co-existence of Hominin Species
« Reply #14 on: June 11, 2016, 08:29:41 AM »
No, but I will when the time presents itself.
He stirred up some academic shit with that one. Facebook to recruit scientific spelunkers? Video documentary to show the process? Allowing full access to all the (~1,500) fossils before they're described scientifically? Analyzing the fossils with a team made up of half established paleontologists and half brand new Ph.D.s? Are you mad!!!!

Loved it.
We 'new atheists' have a reputation for being militant, but make no mistake  we didn't start this war. If you want to place blame put it on the the religious zealots who have been poisoning the minds of the  young for a long long time."
PZ Myers