Clever Corvids: unique beaks for tool use (Introduction)

by dhw, Monday, March 21, 2016, 10:44 (3169 days ago) @ David Turell

dhw: I find it hard to believe that a crow using a stick to obtain its nosh will be unseen by other crows. In any case, there are crows all round where I live, and I see lots of them at a time. Perhaps yours are simply different from ours. I believe some species live in communities of thousands!-DAVID: Hyperbole won't do! I've seen flocks of birds as they migrate. Our crows don't flock.-A quick google has come up with the following:
“Crows have been congregating in large roosts in the fall and winter for as long as there have been crows. Crow roosts can range from small scattered roosts of under one hundred individuals to the spectacularly large roosts of hundreds of thousands, or even more than a million crows! A roost in Fort Cobb, Oklahoma was estimated to hold over two million crows (Gerald Iams, 1972, State of Oklahoma Upland Game Inventory W-82-R-10). Most roosts are much smaller, but roosts of tens of thousands are common.” -dhw: And yes, I believe we inherited aggression, greed, territorialism from our fellow animals, just as we inherited parental love, social structures, and the need to explore.
DAVID: I think they are parallel developments. Do we have specific genes for greed, aggression, etc.? No. Genes are the tools of evolution.
dhw: Evolution is not confined to genes. You have already devoted several threads to the evolution of language, for which there is no known gene. Here we are talking about the evolution of behaviour....If you believe in common descent, you can hardly argue that they are “parallel” developments: they have remained constant right back to whatever ancestry you can think of.
DAVID: Since the simplest parts of our brain function are similar, I think the emotions we see, fear, interest, aggression, etc. can be common, but I'm not at all sure we evolved ours from the organisms that preceded us, but instead developed our own forms of them.-Every species develops its own forms of behaviour, or its own ways of surviving and/or improving. I would suggest that is how evolution works. In the case of homo sapiens, the developments are so sophisticated that some folk don't even recognize that sending tanks into a neighbouring country is a development from Max the monkey snatching a banana from sister Minnie.