2006-09-30 09:20:00 · 17 answers · asked by Anonymous in Science & Mathematics ➔ Biology
They fit their niche perfectly. No pressure to change much.
Aloha
2006-09-30 09:21:17 · answer #1 · answered by Anonymous · 6⤊ 0⤋
Jurassic animal is moe of a tern of phrase than an accurate scientific expression. They are called jurassic because their current day form is likely to the same as it was during the Jurassic period (150-200 million years ago). The lack of selection pressure (e.g. no predators, plenty of food) means that they have not had to adapt and hence have retained a constant phenotype.
2006-10-02 04:04:10 · answer #2 · answered by Anonymous · 1⤊ 0⤋
They're not completely Jurassic animals. there are some changes. But for the most part they have remained the same because they are so well adapted to their environment.
2006-10-02 05:41:21 · answer #3 · answered by Take it from Toby 7 · 1⤊ 0⤋
I'm assuming you mean crocodiles, and I challenge you to show me a living crocodile that's been around since the Jurassic period. The reason they look similar to Jurassic animals is, as others have stated, the relative lack of selection pressure has not caused them to change much.
2006-09-30 11:04:36 · answer #4 · answered by lauriekins 5 · 1⤊ 1⤋
Jurassic crocodile species were Jurassic animals. Modern crocodile species are modern animals. They are not identical. Same with sharks, snails, spiders, roaches, and many other general life forms which were already present in the Jurassic era. There is no individual species living today that was alive in the Jurassic era.
2006-09-30 10:29:36 · answer #5 · answered by PaulCyp 7 · 2⤊ 2⤋
The Discovery Channel just did a show on comets hitting the earth. They believe(nice word) that a comet wiped out the dinosaurs. The reason we still have crocs, gators, turtles, lizards, frogs, toads. salamanders, etc. is due to the fact they could burrow or get in the water. The reason all the aquatic spiecies did not survive is due to the loss of plankton. I hope that answers your question.
2006-09-30 09:30:59 · answer #6 · answered by doggiebike 5 · 2⤊ 0⤋
Because they evolved during the Jurassic period, and have not changed in any way since then. while we humans are supposed to have developed/evolved from a warm blooded creature that was about the size of a mouse during the Jurassic period, or something to that sort of means.
2006-09-30 09:34:04 · answer #7 · answered by Joolz of Salopia 5 · 1⤊ 1⤋
they are perfectly developed for what they need to do and have no other animal which can threaten this position though crocodiles in jurassic times would not have been the same as today nescesarliy
2006-09-30 09:42:52 · answer #8 · answered by Anonymous · 2⤊ 0⤋
They are still similar but the fact remains that they evolved to get to the point they are at now, the fossil record shows this. As well as the numerous crocodilians that are now extinct.... The crocodiles surviving today were the best adapted to surviving in thier environment and so they have changed little over the years.
http://en.wikipedia.org/wiki/Living_fossil
http://en.wikipedia.org/wiki/Crocodilia#Evolution
2006-09-30 09:49:01 · answer #9 · answered by Kelly + Eternal Universal Energy 7 · 1⤊ 1⤋
These god botherers that don't believe in evolution are dangerous. Fuckk off and don't try and impart your whacko beliefs on the rest us. You can't even spell you moron. And for your information Jurassic crocodiles were much bigger than they are now as their prey was larger........ thats evolution in practice asshole..
2006-09-30 09:35:47 · answer #10 · answered by Auld Bawsack 2 · 2⤊ 1⤋
Umm.. because their habitat and eco system hasnt changed enough to warrant them changing yet of course because they are a resilient animal in current form.
2006-09-30 09:51:15 · answer #11 · answered by Jon H 3 · 1⤊ 0⤋