Digit wrote:I don't know whether that is correct or not Beag but I tend always to be interested less in the nuts and bolts and more in the 'why'?
Darwinism stands on the basis that useful, at that perticular time, traits will spread through the species. Fine, so what use was a larger brain to us compared with a Chimp?
The precursor to chimps and hominids lived in a lush Africa. Then millions of years ago, the Great Rift Valley began to form. The climate to the east of the Rift became drier and slowly began to turn to savannah.
That geological event separated us and caused our ancestors to have to begin adapting. Standing erect for instance since more time had to be spent on the ground. The rest is.....still prehistory.
Still doesn't explain how a big brain has any advantage over Chimps etc, and I certainly am not the only person to question the supposed advantage of it.
If the Chimp was around when that happened Beag it would seem to suggest that adaption to survive was not essential, and if it was, the development of a large brain was the course taken by only one group.
Obviously our large brain capacity has allowed us to develop a tech civilisation, but that is a result of, not the cause of our large brain.
Medically, some people have been shown to have minuscule amounts of brain matter without impaired functions.
did you read the link Roy
due to a fluke genetic mutation one day a child was born with a gene that made him have a bigger brain
because of the extra reasoning power this gave him he found a way to fuck more women than the rest of the clan
when his children were born tney also carried this gene
they found a way to fuck more women than the rest of the clan
etc
etc
etc
the end result is you
allegedly
Funnily enough I knew all that before your mum and dad copulated and produced you! The Chimps etc survived with out our brain size. HSN reputedly had bigger brains than us, in case you haven't noticed they are extinct! Their bigger brains didn't seem to help them much did it?
Last edited by Digit on Fri Jan 05, 2007 1:56 am, edited 1 time in total.
Hahn and his research partners examined 110,000 genes in 9,990 gene families that are shared by humans, common chimpanzees (Pan troglodytes), mice, rats and dogs. The scientists found that 5,622, or 56 percent, of the gene families they studied from these five species have grown or shrunk in the number of genes per gene family, suggesting changes in gene number have been so common as to constitute an evolutionary "revolving door."
The researchers paid special attention to gene number changes between humans and chimps. Using a statistical method they devised, the
scientists inferred humans have gained 689 genes (through the duplication of existing genes) and lost 86 genes since diverging from their most recent common ancestor with chimps. Including the 729 genes chimps appear to have lost since their divergence, the total gene differences between humans and chimps was estimated to be about 6 percent.
Hahn said any serious measure of genetic difference between humans and chimps must incorporate both variation at the nucleotide level among coding genes and large-scale differences in the structure of human and chimp genomes. The real question biologists will face is not which measure is correct but rather which sets of differences have been more important in human evolution.
It's probaly the genes we lost that made the difference.
I've read that account before Bruce. Frankly from what I've read in the past I'm not convinced that shear size is as important as the way the brain is wired.
For example, does an Elephant or a Blue Whale have more neurons than we do? If they do then 'wiring' is probably more important than shear size, or are their neurons larger than ours, and does that matter, or are large parts of the brain not actually used but just carry the important bits that are for example?
These brain areas are already known to be involved in the imagining of body movements, suggesting that when the human brain is thinking about the future, it does so in terms of distinct movements and actions that will happen at that point.
Examples from other research include the activation of the part of the brain involved in swinging the arm when volunteers were asked to think about playing baseball.
The test results are in line with other studies of patients who have suffered brain damage in roughly the same areas, and are no longer able to imagine future events.
The researchers wrote: "Perhaps one of the most adaptive capacities of the human mind is the ability to fashion behaviour in anticipation of future consequences.
"Much of our everyday thought depends on our ability to see ourselves partaking in future events."
However, they made clear that further research would be needed to unlock the precise way that brain works when thinking about the future.
Now we just need to catch a Blue Whale and wire him up!
This is a much better discussion than we use to have here regarding religion/faith/ID/evolution and such. I didn't have time to read it all, but what I did read was civil. I miss you guys. I'll get back as I am able. Stay cool!
Something is wrong here. War, disease, death, destruction, hunger, filth, poverty, torture, crime, corruption, and the Ice Capades. Something is definitely wrong. This is not good work. If this is the best God can do, I am not impressed.
Something is wrong here. War, disease, death, destruction, hunger, filth, poverty, torture, crime, corruption, and the Ice Capades. Something is definitely wrong. This is not good work. If this is the best God can do, I am not impressed.
The evolutionary process that led utimately to our modern human brains from a smaller chimp-like brain was a incremental process taking several millions of years. Even so a slight increase in brain size would still hold its advantages. Modern chimps are very sophisticated creatures who use some tools and exhibit some reasoning capacity. I can see how a slightly smarter chimp could have an advantage over his dimmer peers. It seems, however, that the evolutionary niche that chimps occupy is not in want of a smarter chimp as the brain size of chimps has stayed roughly consistant for some millions of years. The chimpanzees' physical adaptaions are perfectly suited for the environment that they inhabit and so there is no environmental pressure for them to evolve biggers brains. So long as that environment remains constant they are unlikely to evolve. Not so with our archaic human and prehuman ancestors. Their changing environment forced evolutionary adaptation upon them. It was either change or go extinct. Remember that bipedalism evolved long before an appreciatively bigger brain did. This is evidence of an ongoing environmental pressure. Organisms well adapted to fill a niche have no need to evolve and don't (think of ancient lineages such as sharks, cockroaches, crocodiles, dragonflies, scorpions and many others to name a few from just the animal kingdom). When the niche changes the organism changes or perishes, it is that simple.
What I find curious is that big brains like ours took so long to evolve. Hundreds of millions of years of evolution failed to produce intelligent creatures until we came along. Other evolutionary adaptations occured mutiple times such as flight, legs to fins, and long necks for grazing. There is nothing obviously special about the environmental changes that took place in Africa at the birth of humanity that would give rise to the adaptation of intelligence. What was the environmental impetuous that led to intelligence in us and not in earlier creatures? Our intelligent brains have turned out to be a super adaptaion, propelling us to the top of the food chain and beyond. Only now, as we have become too dominant and sucessful a species, has our super adaptation become somewhat of a liability. And if we can get past our current problems of overpopulation, human environmental degradation, and the nightmare of armageddon scale warfare our good brains should serve us on into the future. So why didn't intelligence evolve before? Curious and interesting stuff.
