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| Science Forum Index » Anthropology - Paleo Forum » Early hominids in grassland-dominated ecosystems... |
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| Gerrit Hanenburg... |
 Posted: Wed Oct 21, 2009 11:24 am |
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http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0007199
Abstract
Background
Major biological and cultural innovations in late Pliocene hominin
evolution are frequently linked to the spread or fluctuating presence
of C4 grass in African ecosystems. Whereas the deep sea record of
global climatic change provides indirect evidence for an increase in
C4 vegetation with a shift towards a cooler, drier and more variable
global climatic regime beginning approximately 3 million years ago
(Ma), evidence for grassland-dominated ecosystems in continental
Africa and hominin activities within such ecosystems have been
lacking.
Methodology/Principal Findings
We report stable isotopic analyses of pedogenic carbonates and
ungulate enamel, as well as faunal data from ~2.0 Ma archeological
occurrences at Kanjera South, Kenya. These document repeated hominin
activities within a grassland-dominated ecosystem.
Conclusions/Significance
These data demonstrate what hitherto had been speculated based on
indirect evidence: that grassland-dominated ecosystems did in fact
exist during the Plio-Pleistocene, and that early Homo was active in
open settings. Comparison with other Oldowan occurrences indicates
that by 2.0 Ma hominins, almost certainly of the genus Homo, used a
broad spectrum of habitats in East Africa, from open grassland to
riparian forest. This strongly contrasts with the habitat usage of
Australopithecus, and may signal an important shift in hominin
landscape usage. |
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| Lee Olsen... |
| Posted: Thu Oct 22, 2009 7:17 am |
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On Oct 22, 6:36 am, Marc Verhaegen <m_verhae... at (no spam) skynet.be> wrote:
[quote]C4 "grasses" is misleading. C4 is more likely water-loving sedges. Every time
I read an article that talks about C4 "grasses" I reread over and over but can
never find why they have come to the conclusion that the C4 are "grasses".
--Falasha
[/quote]
I guess Falasha has been reading the wrong literature:
What do stable isotopes tell us about hominid
dietary and ecological niches in the pliocene?
J. A. Lee-Thorp , M. Sponheimer , N. J. van der Merwe
International Journal of Osteoarchaeology
Volume 13, Issue 1-2 , Pages 104 - 113
"By now a reasonable set of carbon and oxygen isotope data from tooth
enamel
has been accumulated for South African Plio-Pleistocene hominids and
associated
fauna. Almost all individuals measured, independent of species and
importantly,
environment, show significant C4 dietary inputs with some individuals
showing
very substantial C4 inputs. This implies interactions with grassy
environments
for a period of well over a million years, a period that saw
environments in southern
Africa shift from closed woodlands to more open, grassy landscapes."
and
"Carbon isotope analysis alone is unable to permit the important
distinction between
direct consumption of grasses, or indirect consumption via grass-
eating animals, such
as small vertebrates and invertebrates." |
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| Marc Verhaegen... |
| Posted: Thu Oct 22, 2009 7:36 am |
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Guest
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[quote]C4 "grasses" is misleading. C4 is more likely water-loving sedges. Every time
I read an article that talks about C4 "grasses" I reread over and over but can
never find why they have come to the conclusion that the C4 are "grasses".
--Falasha[/quote]
Yes, I think we need combinations of isotopic data (C, N, O), and
considerations of different diets (incl.different aquatic diets).
[quote]http://www.plosone. org/article/ info%3Adoi% 2F10.1371% 2Fjournal.
pone.0007199
Background:
Major biological & cultural innovations in late Pliocene hominin evolution
are frequently linked to the spread or fluctuating presence of C4 grass in
African ecosystems. Whereas the deep sea record of global climatic change
provides indirect evidence for an increase in C4 vegetation with a shift
towards a cooler, drier & more variable global climatic regime beginning c 3
Ma, evidence for grassland-dominated ecosystems in continental Africa &
hominin activities within such ecosystems have been lacking.
Methodology/ Principal Findings:
We report stable isotopic analyses of pedogenic carbonates & ungulate
enamel, as well as faunal data from ~2.0 Ma archeological occurrences at
Kanjera South, Kenya. These document repeated hominin activities within a
grassland-dominated ecosystem.
Conclusions/ Significance:
These data demonstrate what hitherto had been speculated based on indirect
evidence: that grassland-dominated ecosystems did in fact exist during the
Plio-Pleistocene, and that early Homo was active in open settings.
Comparison with other Oldowan occurrences indicates that by 2.0 Ma hominins,
almost certainly of the genus Homo, used a broad spectrum of habitats in
E.Africa, from open grassland to riparian forest. This strongly contrasts
with the habitat usage of Australopithecus, and may signal an important
shift in hominin landscape usage.
[/quote]
That relatives of ours along waterways sometimes butchered savanna bovids
(eg, drowned & trample when crossing rivers?) doesn't contradict AAT
(littoral Homo ancestors once). To the contrary: stone tool use was
probably first used in opening shellfish etc., as we see in sea otters.
--marc |
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| deowll... |
| Posted: Thu Oct 22, 2009 11:17 pm |
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Guest
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"Marc Verhaegen" <m_verhaegen at (no spam) skynet.be> wrote in message
news:C7062C72.1BEEB%m_verhaegen at (no spam) skynet.be...
[quote]C4 "grasses" is misleading. C4 is more likely water-loving sedges. Every
time
I read an article that talks about C4 "grasses" I reread over and over
but can
never find why they have come to the conclusion that the C4 are
"grasses".
--Falasha
Yes, I think we need combinations of isotopic data (C, N, O), and
considerations of different diets (incl.different aquatic diets).
http://www.plosone. org/article/ info%3Adoi% 2F10.1371% 2Fjournal.
pone.0007199
Background:
Major biological & cultural innovations in late Pliocene hominin
evolution
are frequently linked to the spread or fluctuating presence of C4 grass
in
African ecosystems. Whereas the deep sea record of global climatic change
provides indirect evidence for an increase in C4 vegetation with a shift
towards a cooler, drier & more variable global climatic regime beginning
c 3
Ma, evidence for grassland-dominated ecosystems in continental Africa &
hominin activities within such ecosystems have been lacking.
Methodology/ Principal Findings:
We report stable isotopic analyses of pedogenic carbonates & ungulate
enamel, as well as faunal data from ~2.0 Ma archeological occurrences at
Kanjera South, Kenya. These document repeated hominin activities within a
grassland-dominated ecosystem.
Conclusions/ Significance:
These data demonstrate what hitherto had been speculated based on
indirect
evidence: that grassland-dominated ecosystems did in fact exist during
the
Plio-Pleistocene, and that early Homo was active in open settings.
Comparison with other Oldowan occurrences indicates that by 2.0 Ma
hominins,
almost certainly of the genus Homo, used a broad spectrum of habitats in
E.Africa, from open grassland to riparian forest. This strongly contrasts
with the habitat usage of Australopithecus, and may signal an important
shift in hominin landscape usage.
That relatives of ours along waterways sometimes butchered savanna bovids
(eg, drowned & trample when crossing rivers?) doesn't contradict AAT
(littoral Homo ancestors once). To the contrary: stone tool use was
probably first used in opening shellfish etc., as we see in sea otters.
--marc
[/quote]
Some chimps use them to open nuts. The hammer and anvil may be LCA tech. |
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| jerry warner... |
| Posted: Fri Oct 23, 2009 1:39 am |
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Guest
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Marc Verhaegen wrote:
[quote]C4 "grasses" is misleading. C4 is more likely water-loving sedges. Every time
I read an article that talks about C4 "grasses" I reread over and over but can
never find why they have come to the conclusion that the C4 are "grasses".
--Falasha
Yes, I think we need combinations of isotopic data (C, N, O), and
considerations of different diets (incl.different aquatic diets).
http://www.plosone. org/article/ info%3Adoi% 2F10.1371% 2Fjournal.
pone.0007199
Background:
Major biological & cultural innovations in late Pliocene hominin evolution
are frequently linked to the spread or fluctuating presence of C4 grass in
African ecosystems. Whereas the deep sea record of global climatic change
provides indirect evidence for an increase in C4 vegetation with a shift
towards a cooler, drier & more variable global climatic regime beginning c 3
Ma, evidence for grassland-dominated ecosystems in continental Africa &
hominin activities within such ecosystems have been lacking.
Methodology/ Principal Findings:
We report stable isotopic analyses of pedogenic carbonates & ungulate
enamel, as well as faunal data from ~2.0 Ma archeological occurrences at
Kanjera South, Kenya. These document repeated hominin activities within a
grassland-dominated ecosystem.
Conclusions/ Significance:
These data demonstrate what hitherto had been speculated based on indirect
evidence: that grassland-dominated ecosystems did in fact exist during the
Plio-Pleistocene, and that early Homo was active in open settings.
Comparison with other Oldowan occurrences indicates that by 2.0 Ma hominins,
almost certainly of the genus Homo, used a broad spectrum of habitats in
E.Africa, from open grassland to riparian forest. This strongly contrasts
with the habitat usage of Australopithecus, and may signal an important
shift in hominin landscape usage.
That relatives of ours along waterways sometimes butchered savanna bovids
(eg, drowned & trample when crossing rivers?) doesn't contradict AAT
(littoral Homo ancestors once). To the contrary: stone tool use was
probably first used in opening shellfish etc., as we see in sea otters.
[/quote]
all at 2:34pm UTC 2004 BP. Science can play GAWD
too!
[quote]
--marc[/quote] |
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| deowll... |
| Posted: Sat Oct 24, 2009 5:54 pm |
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| deowll... |
| Posted: Sat Oct 24, 2009 6:13 pm |
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"deowll" <deowll at (no spam) gmail.com> wrote in message
news:hc0434$b1u$1 at (no spam) news.eternal-september.org...
[quote]http://www.sciencemag.org/cgi/content/full/326/5949/60-b
[/quote]
If that is what they are calling a closed canopy forest the trees aren't
very large and the canopy isn't all that closed with a lot of ground cover.
Any decent sized animal is going to have to walk between trees.
I have also noted that the big toe is so large that if drawn in next to the
foot it just might be able to use it to toe off. In fact it might have used
it any way if it walked toes out. The big toe on this animal may not be all
that much shorter than Lucy's or a hobbits.
I hadn't thought much about that 4' tall 110 pounds before but that is about
twice what a human child that height would weigh based on an old human
growth scale. Short but powerful. |
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| RichTravsky... |
| Posted: Mon Oct 26, 2009 12:05 am |
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Guest
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Marc Verhaegen wrote:
[quote]
C4 "grasses" is misleading. C4 is more likely water-loving sedges. Every time
I read an article that talks about C4 "grasses" I reread over and over but can
never find why they have come to the conclusion that the C4 are "grasses".
--Falasha
Yes, I think we need combinations of isotopic data (C, N, O), and
considerations of different diets (incl.different aquatic diets).
http://www.plosone. org/article/ info%3Adoi% 2F10.1371% 2Fjournal.
pone.0007199
Background:
Major biological & cultural innovations in late Pliocene hominin evolution
are frequently linked to the spread or fluctuating presence of C4 grass in
African ecosystems. Whereas the deep sea record of global climatic change
provides indirect evidence for an increase in C4 vegetation with a shift
towards a cooler, drier & more variable global climatic regime beginning c 3
Ma, evidence for grassland-dominated ecosystems in continental Africa &
hominin activities within such ecosystems have been lacking.
Methodology/ Principal Findings:
We report stable isotopic analyses of pedogenic carbonates & ungulate
enamel, as well as faunal data from ~2.0 Ma archeological occurrences at
Kanjera South, Kenya. These document repeated hominin activities within a
grassland-dominated ecosystem.
Conclusions/ Significance:
These data demonstrate what hitherto had been speculated based on indirect
evidence: that grassland-dominated ecosystems did in fact exist during the
Plio-Pleistocene, and that early Homo was active in open settings.
Comparison with other Oldowan occurrences indicates that by 2.0 Ma hominins,
almost certainly of the genus Homo, used a broad spectrum of habitats in
E.Africa, from open grassland to riparian forest. This strongly contrasts
with the habitat usage of Australopithecus, and may signal an important
shift in hominin landscape usage.
That relatives of ours along waterways sometimes butchered savanna bovids
(eg, drowned & trample when crossing rivers?) doesn't contradict AAT
[/quote]
Relatives of ours butchered animals elsewhere too. Good opportunists.
[quote](littoral Homo ancestors once). To the contrary: stone tool use was
probably first used in opening shellfish etc., as we see in sea otters.
[/quote]
Monkeys use rocks too. No water needed. |
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