Originally posted by Barcs
Sorry I have to correct you. Homo neanderthalensis appeared BEFORE homo sapiens in the fossil record. Yes, they are subspecies and were living
cousins of homo sapiens who shared a common ancestor and they did breed together eventually, but there is still a 150,000 year difference from when
Neanderthal emerged (around 400,000 years ago) and when Homo sapiens emerged (250,000 years ago). If you want to call that virtually the same time,
then sure. I don't see that at all. I see a group migrated out of Africa and evolved into neanderthals. The ones who stayed EVENTUALLY became homo
sapiens. It certainly didn't happen over night or at the same time.
I stated that they emerged at
nearly the same time, and I specified later in my response that
neanderthalensis was here first (though my
previous time references were a little off).
Heidelbergensis dies off at the same time as
neanderthalensis emerges, in the same
regions; 350,000 years ago. 150,000 years pass before
sapien emerges (200,000 years ago). They co-exist for 170,000 years, at which point
neanderthalensis dies out (30,000 years ago).
So your arguments is that the brain developed faster in homo sapiens than any other hominid ancestor? Sorry to rain on the parade, but the
average brain size for Heidelbergensis was 1200cc. Comparatively Neanderthalensis was 1450 cc and homo sapien was 1350 cc. That is certainly not any
more rapid than the difference between any other hominid. Even if you look at late homo erectus their brain size was 1100cc give or take.
Now even if this sudden change did happen, it wouldn't discount evolution. Evolution isn't on a time table. It just keeps happening and the
environment dictates the speed. Sudden changes in environment lead to faster extinction and therefor evolution and emergence of new
species.
Again, I'm referring specifically to the development of the the frontal lobe (prefrontal cortex) as well as the key region of the brain responsible
for language, specifically speech; Broca's area. I don't have the exact citations providing an exact time-line of their respective development
progressions at hand, but I will provide them here shortly; as soon as I go through my references. I hear what you're saying about evolution not
being on a static timeframe, that environmental factors influence its rate and extent. Also, I want to clarify that I never said or meant to imply
that any of this "discounts" evolution. Evolution is a proven, demonstrable phenomena throughout the natural world and I think it accounts for 99% of
the "human story". I am not sufficiently satisfied that evolution, on its own, explains, what I see as the rapid emergence of human consciousness
(marked by the advancement of the prefrontal cortext, and language centers in the brain). Since I don't have those citations handy, I'll hold off on
saying anything else until I post them later tonight.
You gotta be kidding me. You use an insult based google search site to search for the broad term "human evolution" and expect me to search
through all of that to find the specifics of what you are talking about? I am VERY familiar with human evolution, I just keep hearing claims of this
alleged rapid change, which is just the same as most hominids change going back 2.5 million years.
I'm sorry. I didn't mean to come off as insulting or patronizing. I will go through my references and post specifics and citations related to the
development of the prefrontal cortex and language centers, hopefully illustrating what I'm talking about.
edit on 6/5/2012 by draco49 because:
(no reason given)