the bests short answer is around 75 million years ago after the meteor smashed into what is now the yukatan penensula (my spelling is bad I know, no spell check) southern mexico, a large cloud of dust blocked out the sun preventing vegetative growth on the scale needed to supply the large reptiles (dinosaurs) and bird predocesors with food, so they died out, however the smaller reptiles and birds lived along with a couple of small tree dwelling mamals I forgot their name but when I was in school there we two specific ones, from them mammals evolved to what we are, 10 million years ago the evolutionary tree split and that is our last connection to what is now the gorilla, and five million years ago the line that became humans split with the line that became chimpanzees, then there have been a number of evolutionary stages for the current humans, homo habulus homo erectus and homo sapian (which we are today) neandertal was not a predocessor to us but its own separate brach that died out to to competition with homo erectus, the birds and lizards I am unsure of in terms of their evolutioanry journey
2006-10-04 03:18:37
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answer #1
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answered by ninja cat 4
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Well, there was apparently a nice big chunk of rock that hit the earth, ending the slow decline of dinosaurs with a final extinction...maybe. Birds persisted, now known to be direct descendents of dinosaurs. So perhaps the end wasn't as sudden and dramatic as commonly portrayed by catastrophe enthusiasts.
In any event, the removal of the last few dinosaur species plus the worldwide climatic upheaval from Deep Impact unsettled things all over the world. It always takes a while for the ecosystem to stabilize after an event like that. Those species which survive found themselves with a blank slate, and started to rewrite the rules.
There is a concept known as radiation, which is basically a big spurt in a type of living thing. One is geographic, where all of a sudden a species finds itself able to go a heck of a lot farther, perhaps into new continents. Another is adaptive radiation, where a species finds a bunch of different roles to play in the environment. Think of radiation like a paper fan, the folded paper is bunched up in your hand, and then each panel radiates out from that central point.
So a few lucky species got a fresh start, finding both new geographic ranges and new ecological niches to fill. When a population covers a huge range, there is always variation in climate and food and predators over that range, and so different groups within that species have different environmental factors that they have to adapt to. Also, if one group becomes isolated slowly mutations start building up, which is called genetic drift.
Actually, though, this process of evolution isn't all that drawn out, apparently. Long periods of stability in the fossil record are broken by sudden bursts of variability, which then settle down into new, stable forms. This is called punctuated equilibrium. The most successful forms quickly dominate in a population after an environmental shift.
Just after the dinos died out, there really was no coherence in the fossil record for a few million years, or perhaps there just aren't that many fossils to find. The conditions for fossils to be formed actually are pretty uncommon, so not all periods are equally represented in the fossil record. For example, Indiana where I live has nothing from the entire Mesozoic era because all the rocks from that time are eroded away. Other states around us may have dino fossils, but we don't. When we do have fossil records, mammals had radiated geographically and then they radiated adaptively into all the roles in the environment we see today.
India slammed into Asia, Africa slid into its current position, Australia did likewise, North and South America drifted together but further apart from Europe and Africa, a long series of ice ages began, each of which radically altered the appearance of both the earth and the environment.
Then a new species of primate started to appear, one which was incredibly mobile and used tools. This primate persisted for over a million years, before being overtaken by a daughter species that had developed a whole new way of adapting to changes by rearranging the environment to suit itself and being smart enough to fill whatever role could be found in the environment. And that brings us to the modern world.
2006-10-04 06:51:41
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answer #2
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answered by almethod2004 2
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Fossils of dinosaurs are mostly in the upright position. They died not of starvation but of a sudden catastrophe. They probably died in the great flood in which Noah's ark was noted. They are believed to have been suddenly covered by mud which prevented their decomposing like if a cow died in a field. This is estimated by the best scientists of today as less than 10,000 years ago. See the "Illustrated Origins Answer Book" by Paul S. Taylor. There are over 50 pages of scientific bibliography and lots of good information.
2006-10-04 05:28:38
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answer #3
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answered by Big Bama Fan 2
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Pompei, was covered in vulcanic ashes... There are scars on earth, from different origins and incidents... When disaster strikes, all previous life is lost as we know it... Perhaps 10 people would survive the Nuclear holocaust... Being not of biological origin would helpa lot.. so what would survive chance 0% a computer more likely.
Nothing in life is what it seems....... Perhaps Dinosaur is figurative speach for something not quite there yet... perhaps we find the lost world... On an undiscovered Island wich seems frozen in time... But then again isn't our world bigger then we thought before.... The best joke I think is the one I had to learn at school Earth is 40.000 km around instead....... GAIA was that small yeah. Hollywood should be ashamed of it's alliance with the wrong timelords falsehood for all ..... I who has no titel to defend preferably, would love Gelredome to host a Festival I'd like permission for. The one Flag... One World Mission is my castle full of BS... Dreamer yes, but not with society as it is wouldn't you say...... Hilary Clinton for Internet president is my opinion...... even though I must say, she has a tough cookie against her with a mind like wildfire betamaxie_unalove... wonder who that is miracleworx too.... who's smartmiracle... What happens whent they would be exterminated on false accusation like it is today .......
2006-10-04 05:41:33
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answer #4
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answered by Anonymous
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The mammals were given a chance to florish.If it were not for the extinction of the dinosaurs,they say mankind as well as most other mammals might not have come into existance. The dinosaurs were eating them.
2006-10-04 07:48:54
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answer #5
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answered by dewhatulike 5
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they had a big funeral. I don't know and neither do any of these over educated idiots that say man evolved from a rock or a monkey. This isn't possible.
2006-10-04 05:28:19
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answer #6
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answered by Gunslinger 2
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the human race began just after the human long jump
2006-10-04 05:20:08
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answer #7
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answered by soarsy 1
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slap yur self
evolution ring a bell
2006-10-04 05:24:19
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answer #8
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answered by lv23smurf 3
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some one ate them
2006-10-06 02:41:23
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answer #9
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answered by John B 4
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They decomposed.
2006-10-04 05:27:49
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answer #10
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answered by paulrasjr 1
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