They have to be the closest looking thing to a land living animal(dog).
In the long road of evolution are seals adapting to life back in the water or are they adapting to life out of it?
Thoughts and proof please
2006-10-19 03:06:38 · 10 answers · asked by Jay 3 in Science & Mathematics ➔ Zoology
According to fossil evidence, seals now are going back to the sea. Several millions of years ago, they were tiger-like animals.
Another proof is that they spend most of their lives in the sea, they only come out to raise their offspring.
2006-10-19 07:46:26 · answer #1 · answered by Peter pan 6 · 0⤊ 0⤋
It is a false assumption that evolution is always "going somewhere"; much of the power of natural selection is keeping things the same. Seals are descended from land-dwelling ancestors, but it doesn't mean they are turning into fully marine creatures. There are already fully marine mammals - whales, and seals can't compete in that environment. They also obviously can't match land animals in their own niche. Any evolutionary trend to move in on eaither environment will result in extermination.
However, they can access areas (rocky foreshores, beaches, ice floes) difficult or impossible for whales or wolves.
Pinnipeds (seals, sea-lions, walrusses) are not "halfway" animals, they are fully adapted to their lifestyle.
If all the whales die out, seals may well give rise to a new fully marine mammal as niche will become available - but others will remain right where they are.
2006-10-20 01:04:00 · answer #2 · answered by Paul FB 3 · 0⤊ 0⤋
The evolutionary history of seals began in the sea, made its way up onto the land in the mid-late Palaeozoic, then returned to the sea in the early to mid Cenozoic.
Sea > Land > Sea...
Its entirely possible that some might be moving back out of it again now... since things can be random and unstable that way. Theres no way to know where they're going to go from here... either becoming even more aquatically adapted like dolphins, or less so enough that they can emerge properly onto land again.... but I've pretty much answered your question.....
I hope that satisfies.
2006-10-19 03:16:55 · answer #3 · answered by Anonymous · 2⤊ 0⤋
Seals are evolutionarily partly returned to the sea. Proof? They're mammals - and mammals evolved as small *land-living* rodent-like things during the time of the dinosaurs. So seals, sealions and walruses are all adapted to living in the sea, but evolved from a land-living ancestor. Just like whales and dolphins.
2006-10-19 03:16:56 · answer #4 · answered by caladria 2 · 0⤊ 0⤋
On the whole i agree that they don't actually have to be 'going' anywhere. However, seal pups are very vulnerable to predators, crashing waves and testosterone-fuelled male seals for the few weeks that they are on the beach. If some change in seal biology meant that pups could spend less time on land, then that might well be an evolutionary advantage to those seals (meaning more chance of breeding success). In those terms, there is some pressure for seals to be more aquatic than they are.
2006-10-21 11:46:28 · answer #5 · answered by SteveNaive 3 · 0⤊ 0⤋
mammals as a group developed some 250 million years ago, as landliving animals. ALL sealiving mammals like whales and seals have gone back to the sea.
2006-10-19 03:19:16 · answer #6 · answered by wolschou 6 · 0⤊ 0⤋
Are seals going back to the sea or comeing out?
Which way are they facing? That would be a good indication!
2006-10-19 03:08:48 · answer #7 · answered by Christ 3 · 1⤊ 0⤋
They are only a branch on the evolution tree; living in both worlds.
2006-10-19 03:17:57 · answer #8 · answered by Anonymous · 0⤊ 0⤋
They have evolved to do both. At what point did a dog have it off with a fish is what I want to know?
2006-10-19 03:15:19 · answer #9 · answered by Anonymous · 0⤊ 1⤋
Wow, cant believe you got so many sensible answers to this question. Well done you!
2006-10-19 05:40:00 · answer #10 · answered by buttercup 3 · 1⤊ 0⤋