Re: Reducted Olfaction in Humans - For a scavenging species in woodland/savannah?



On Dec 29, 4:13 pm, RichTravsky <traRvE...@xxxxxxxxxxxxxxx> wrote:
Algis Kuliukas wrote:

Gilad, Y., Man, O., Glusman, G. A comparison of the human and
chimpanzee olfactory receptor gene repertoires. Genome Research 15 (2):
224-230, (2005).

[..]

They carried material for stone tools for several kilometers, why
not meat?

Meat is one thing, but brains? bone marrow?

Secondly, this proposed move towards greater carnivory is directly
contradicted by the simultaneous phenomenon of dental reduction,
especially canines. That our species would be the first ever to evolve
greater carnivory whilst at the same time undergoing dental reduction
feels like special pleading to me. Appeals that it is likely to have
been explained by increased technology - such as cooking or cutting
implements - are possible solutions but there is a far more
parsimoniois one (see below.)

Another use for stone tools!

So they ground the meat into a pulp with their sophisticated stone
tools and then sucked up the gunk.

Thirdly, for a species that is supposed to have undergone a period of
evolution where scavenging for food was an essential part of their
behaviour, a REDUCTION in olfactory capability is exactly the opposite

Oh? Just follow the vultures...

But why LOSE the capability?

of what one would predict. Again, it would represent another unique
example of evolution - more special pleading. That a scavenging
species effectively lost its olfactory capability - not only compared
to species that are adapted to scavenging (e.g. Canids - which have
olfactory capability thousands of times better than us), but even
compared to our nearest relatives, the chimps and gorillas, just does
not make sense. We, remember, are the ones that came down from the
trees - and yet, compared to them, we have lost our sense of smell.

No, we haven't.

 http://www.berkeley.edu/news/media/releases/2005/08/29_smell.shtml
 Study shows humans have ability to track odors, much like bloodhounds

 29 August 2005

 BERKELEY – Though humans may never match the tracking ability of dogs, we
 apparently have the ability to sniff out and locate odors, according to a
 new study by scientists from the University of California, Berkeley.
 ...
 Porter, Sobel and their colleagues reported the results in the August 18 issue
 of the journal Neuron.

 In a review appearing in the same issue of the journal, Jay A. Gottfried of
 the Department of Neurology at Northwestern University's Feinberg School of
 Medicine noted that the UC Berkeley findings open numerous avenues for further
 research. "Finally, what are the implications for the Provençal truffle hunt?"
 he wrote, only partly tongue-in-cheek. "In the traditional world of the truffle
 forests, the dog (or pig) is king. The evidence presented here suggests that
 humans are every bit as well equipped to carry out the search."

But the whole point of the article I posted was to show that human
have LOST olfactory receptors (better evidence than any subjective
study) compared to CHIMPANZEES. It amazes me how you find it so easy
to miss simple points like this.

And scavenging does not have to depend on smell. As I said, follow the
vultures. Competition?

 http://www.ncbi.nlm.nih.gov/pubmed/18842286
 J Hum Evol. 2008 Dec;55(6):1031-52. Epub 2008 Oct 8.Click here to read Links
 Taphonomic perspectives on hominid site use and foraging strategies during
 Bed II times at Olduvai Gorge, Tanzania.
 ...
 Carcass processing by hominids in such habitats would certainly have enticed local
 groups of carnivores. The ability to butcher and control carcasses under these
 circumstances speaks to the superior competitive abilities of H. erectus
 during upper Bed II times.
 ...

But why LOSE olfactory capability compared to chimps?

Algis Kuliukas
.



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