Vertebrates Became Predators By Tweaking the Neural Crest (phys.org) 15
An anonymous reader quotes a report from Phys.Org: Caltech scientists have discovered that a population of embryonic stem cells called neural crest cells may help explain how vertebrates progressively evolved a more and more efficient head. Neural crest cells originate within the developing central nervous system before migrating throughout the embryo. They are a major player in the development of the jaws and other important components of the head and face, making them a good candidate for a role in vertebrate head evolution.
The study, led by postdoctoral scholar Megan Martik, began by comparing the genetic makeup of lamprey neural crest with that of chicken embryos. The team discovered that the lamprey neural crest cells lacked important genes that are present in the head neural crest of birds and mammals, and critical for making advanced structures like the jaw. The team wondered how the neural crest ultimately acquired the genes. To look for clues, they examined the neural crest genes of animals that have jaws, such as sharks and zebrafish, and evolved after lamprey but well before chickens and other birds. Martik and her colleagues found that the genetic program that helped to make the head more sophisticated was created by the progressive addition of genes to the neural crest repertoire as the vertebrate tree of life advanced and new species evolved. The study has been published in the journal Nature.
The study, led by postdoctoral scholar Megan Martik, began by comparing the genetic makeup of lamprey neural crest with that of chicken embryos. The team discovered that the lamprey neural crest cells lacked important genes that are present in the head neural crest of birds and mammals, and critical for making advanced structures like the jaw. The team wondered how the neural crest ultimately acquired the genes. To look for clues, they examined the neural crest genes of animals that have jaws, such as sharks and zebrafish, and evolved after lamprey but well before chickens and other birds. Martik and her colleagues found that the genetic program that helped to make the head more sophisticated was created by the progressive addition of genes to the neural crest repertoire as the vertebrate tree of life advanced and new species evolved. The study has been published in the journal Nature.
Interesting, yet... (Score:3)
Assuming "predator" means eating other vertebrates, t.he mutation to a set of jaws that eat the flesh of others doesn't seem to be that far off from that of the set of jaws that grind up plant matter.
What is most interesting, is the slim chance of a mutation gaining widespread survival advantage in a species, let alone the entire kingdom.... the sheer number of life forms born every day with a trivial or disadvantaged mutation is staggering.
But thank goodness! Eating proper ribeye is one of life's lasting pleasures.
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"something having to be small enough that you can envelope it."
Didn't know the Post Office was that old!
https://www.merriam-webster.co... [merriam-webster.com]
Re:Interesting, yet... (Score:5, Informative)
There are several jawless solutions to eating plants, modern day urchins are a good example, as are the slugs which plague my garden. The significance of jaws in predation is actually reflected in the fossil record. When jawed fishes started to evolve, they rapidly took over and the dominance of invertebrates with exoskeletons ended abruptly. While there are always multiple factors that go into extinction events, with the addition of a jaw, fish became agile, fast predators capable of crushing the chitin of their prey. The early invertebrates didn't stand much of a chance against the placoderms.
So, while undoubtedly a jaw makes us better herbivores, it's significance to early predators is really what cemented it as a hereditary feature.
And one day... (Score:1)
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I love all the cells crawling around (Score:2)
Predators vs Prey (Score:2)
Prey has eyes on the sides of its head. Predators have eyes on the front of the head.
If only I was a lamprey, I could yawn wider (Score:2, Interesting)
There are hundreds (thousands?) of bioscience journals, each year publishing hundreds of thousands of research papers. Each such paper advances our knowledge, sometimes in big and profound ways, sometimes just small incremental additions to the knowledge base. This is one of those latter types, an interesting and well executed study on a small facet of biology. It does not establish a new branch on the tree of knowledge, just adds a small leaf to a branch of study well established, a small piece of the g
hear that vegans? (Score:1)
We're predators. Well, at the few of us that are vertebrates. My lizard brain demands flesh, preferably fried chicken.
(Spiders, dragonflies, and praying mantis are not plant eaters either)