bluejay writes:
Fine. Except that, strangely enough, the chimpanzee wasn't around until after Homo erectus, so there is no evidence of a 250% brain-mass increase. What does that do to your estimates (don't bother answering that: it's rhetorical. I can do the math myself).
Just in case you can't do the math.....
Chimp ancestors had brains just about the same size as chimps (400-500 cc's). Maybe just slightly different. So it really does nothing to alter my estimates significantly.
bluejay writes:
Also note: why is it such a big deal for the erectus brain to have enlarged so much relative to ours in the same amount of time? You realize that, if just one additional round of cell division occurs in the brain early on, you can double the brain mass, yeah? That could probably be accomplished by a single mutation. That's a 100% increase in a single generation.
Wow, if only it could be true. That evolution stuff really is magic when you can imagine just about anything, but can't demonstrate it with observation and repeatability.
You do realize that the brain is a polygenic trait. In fact it is made up of hundreds of genes. It is highly unlikely that one mutation to a brain gene would do anything to it's relative size. We know from scientific studies that there are vast genetic differences in chimp and human brains. Far more than your one imaginative doubling from a single mutation. Also you are forgeting about all the other traits that are attached and related to the brain that must simultaneously adapt (through additional genetic change) to these genetic changes. Including the skull for an example.
bluejay writes:
Think of this: even the brainiest Homo erectus had only about 75% of the brain mass of the average Homo sapiens, yet, as far as I can ascertain, H. erectus was not significantly smaller than H. sapiens overall. Where we have a 1:50 ratio of brain to body (mass), the biggest-brained H. erectus has only a 1:67 or 1:70 ratio (most have 1:75 or 1:80). Compare to chimpanzee at 1:125.
The first book I was required to read in college was "How to Lie with Statistics". I can show you brain to body mass calculations of homo sapiens that are far worse than 1:125. This statistic in homo sapiens varies widely. But not so with chimpanzees.
bluejay writes:
Do you believe that Homo erectus had the brain power to design and build the Tower of Babel without God's help (surely you believe that God didn't help them)?
First let me discuss brainpower. Yes I beleive that homo erectus had the intellect to build the tower of Babel.
Second, I believe that God helps every human being whether they are in His will or not. He may not have given them the plans to build the structure, but He certainly gave them the intellect and physical capacity to do so.
bluejay writes:
I personally do not. However, this is based more on archaeological evidence and dating techniques that place Homo erectus in sediments wherein only the simplest types of tools are ever found, than it is on a rigorous investigation of neurological capacity. You, no doubt, do not accept this type of co-occurence evidence as meaningful.
Well, I would say that the type of tools has very little to do with intellect. If I took all your tools away, and put you on a desert island by yourself, what would you do for tools? I think they would be very similar to homo erectus tools. The tools you use have nothing to do with intellect. Over time new tools and processes are developed by some individuals. Then they must be spread to others through some sort of economic means. The tools you use have more to do with the total environment as than they do with intellect.
I am not saying that a larger brain doesn't have the capacity for more intellect. We certainly may be more intellectual that homo erectus. But most of us couldn't plan and build a tower either.
™ Version 4.2
