looking for time graph for human evolution

[gib65]

Does anybody have a link to a good time graph depicting human evolution?

 

Thanks.

[Cthulhu]

Does anybody have a link to a good time graph depicting human evolution?

 

Thanks.

 

This one is pretty good' date=' probably not 100% up to date though: http://www.mnh.si.edu/anthro/humanorigins/ha/a_tree.html

 

[img']http://www.mnh.si.edu/anthro/humanorigins/ha/images/bigtree2.GIF[/img]

[gib65]

Thanks Cthulhu.

 

Now I have a follow up question. I don't know if it has a scientific answer (might be more philosophical), but here's the background for it:

 

I'm writing a paper on the evolution of thought, and one of the ideas I'm trying to push is that there have been two major leaps in human thought. The first step was gaining the ability to visualize - that is, withdrawing from the immediate environment and going into the imagination. The second step was gaining the ability to understand abstract concepts - that is, being able to understand things that require transcending simple visual features.

 

I'm thinking that my best bet is to mark the advent of visualization with the advent of tool invention, which would place it around the emergence of homo habilis since the link you provided says tool invention appeared with this species. My thinking is that in order to come up with ideas for new tool designs, it requires withdrawing into the imagination in order to mentally simulate the manipulation of matter (like carving a spear head out of a rock). I argue that this could have happened without the ability to visualize but it would have to rely on accidental discoveries, like accidentally chipping a rock to make it sharp and then noticing how this makes it for effective in cutting. I also think abstract concepts emerged with the advent of homo sapiens. My reason is that abstract concepts should result in the appearance of religious worldviews and rituals, and no other species except homo sapients have participated in this kind of activity.

 

So here's my question: among anthropologists, is there any support for this view? Or would anthropologist say things against it? If the latter, what things would they say? Or is nothing much said about it at all?

 

PS - I realize nothing really "scientific" can be said about this since it requires a lot of speculation, but I'm just wondering if I'm going with or against the commonly accepted view within the anthropological community.

 

I very much appreciate your feedback.