I don't know much about seal biting, but I'm confused about one thing...okay...two things. Okay, many things, but why didn't other species make the jump to water? But more importantly, for me, is I thought that all life sprung from the oceans, i.e, that all mammals began from things that crawled out of the water onto land. Does that mean that seals crawled out and then went back?
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So you determined that seals ancestors, who lived on land, were biters rather than suction or filter feeders? And you got a grant for that?
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Michael Behe and Intelligent Design would beg to differ on this "just so" story based on Darwinian evolution. By taking the discussion down to the molecular level, he would show how many changes would have to occur for such a thing to happen. According to Darwinian theory, this would all happen by chance, each step involving no memory, no sense of being part of a bigger picture, and no purpose. This would mean blind, haphazard mutations somehow leading to new instructions in DNA about the formation of the cells and protein machines that would have to be formed to bring about this wonderful new creature. When viewed this way, this pretty story is mathematically impossible.
From the article, "But how did seals first take the evolutionary dive into the oceans more than 30 million years ago?"
I am not steeped in the paleontological development of pinnipeds but I would argue that their transitional forms sauntered their way into the forms that are displayed today rather than dived. The paleoenvironments these transitional forms exploited were probably the lower reaches of river systems, estuarine zones and possibly shallow inland seas. That way they would avoid the more rigorous requirements of an oceanic existence.
These transitional forms would have had abundant opportunities to utilize the ability of feeding on land and in the nearby aquatic environment. The anadromous food sources in the waters and scavenging on land would have provided abundant resources. That lifestyle would also give them advantages in escaping predators.
I live just above the tidewater break on a coastal river. I have had numerous opportunities to watch harbor seals biting, catching and thrashing salmon/steelhead/bluebacks during the runs. Their forebears must have been biters. That's why I call them sea dogs.
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I am sorry for saying this, but this is a pretty vague explanation: they were successful in the sea, because they already knew how to bite (what? a bird?) when still being land dwelling carnivorous creatures? If so, can we explain the successful entry into the sea of the ancestors of sea lions by their ability to balance a ball on their noses? And what about dolphins? Their ancestors knew how to do a backside flip while running on land?
I might be wrong but it seems to me there is some information missing in this article.
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On behalf of the GOP, let me point out that you forgot to provide the "alternative fact" that the first seal fell off Noah's ark and had learn to swim in a hurry in order to survive.
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https://dosits.org/galleries/audio-gallery/marine-mammals/pinnipeds/crabeater-seal/
See the above for pics of teeth of crab eater seal that strains krill for food. I remember these fascinating teeth from sorting through specimens at the New York State Museum in Albany, NY years ago when I worked briefly as an assistant to Dr. Reilly.
It would have been nice to have described more fully what actually this primal 'bite' strategy was.
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@James F Traynor
That is one nifty site! Thanks for the link.
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@James F Traynor
Outstanding link.
"a particular biting style helped the marine mammals’ landlubber ancestors move into the oceans".
It is unclear that biting "helped". The study seems to identify that biting was the prominent mode of eating for seals' ancestors. Subsequently, they evolved filtration and sucking. Did biting "help" them make the transition to the ocean? There is no evidence of that. In fact, the fact that other forms of eating later evolved suggests that biting was more a hurdle than a help and was shed in favor of other means of eating.
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What aspects of seals' biting style made them more adaptable to an aquatic environment than other animals, which also bite?
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The more pressing question: What aspect of natural selection resulted in the ability to balance beach balls on their noses?
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@Charlie B It was established that they once lived on the land-sea interface (beach) and we know they don't have hands! How else are they going to carry a beach ball?
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