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Today's Dinosaur News
1
I for one, stand with First Nations people of Canada in keeping our Hadrosaurs in Canada and away from spirit-hating American occupation forces.
Saber Toothed Squirrel for the win!
(now we know why dogs chase squirrels)
Saber Toothed Squirrel for the win!
(now we know why dogs chase squirrels)
2
Thanks Mary. What kind of nuts was that squirrel eating, anyway? It must have preyed on something pretty freaking tough. Scientists proved that saber toothed cats
were adapted to puncturing the carotid artery on buffalo. Maybe they preyed on baby sauropods.
were adapted to puncturing the carotid artery on buffalo. Maybe they preyed on baby sauropods.
3
Thanks for a nice science post that doesn't attract trolls (and not the fun kind from the Norwegian movie either).
Cool about the saber-toothed squirrel.
Cool about the saber-toothed squirrel.
4
Sauropods, for the most part, HAD to have been migratory. They filled more or less the role that elephants do today, and that means that they put a lot of strain on plant life wherever they went. It;s nice to see the isotopic data backing this up.
And it's not a saber-toothed squirrel; it's a saber-toothed early mammal only very distantly related to rodents.
And it's not a saber-toothed squirrel; it's a saber-toothed early mammal only very distantly related to rodents.
5
It makes sense. Just because the organisms in the niche change, doesn't mean that the behavioral pressure that the niche imposes upon organisms necessarily changes; folllow the food is a constant. The urge to migrate is innate in many species, how to migrate successfully often has to be taught from parent to offspring. Birds, wildebeest, bison, dinosaurs, nature doesn't throw away genes, it just turns them on or off occasionally.
6
@5: ACTUALLY, migration among elephants and sauropods is likely to be homoplasious (the result of convergent evolution) rather than homologous (shared due to inheritance from a common ancestor). They are fairly distantly related, and migration is a fairly complex trait.
Genes are switched on and off (DNA methylation), but this is on the level of an individual organism, not a species.
Genes are switched on and off (DNA methylation), but this is on the level of an individual organism, not a species.
8
@6, I get your point and understand convergent evolution, though am probably not as expert as you. Is it not true though that most organisms have far more genes in their chromosomes than are actually used? I have read that they are "legacies" of evolution and under certain cicumstances can, via mutation, become active in different ways, and if beneficial to the species as a whole are passed on as active. I find the subject fascinating and would like to know more.
9
@8: Many genes are suppressed or otherwise inactive, but can manifest a phenotype due to mutation or a change in the signal. This explains why whales occasionally grow small hindlimbs.
Pretty much every gene in an organism's genome is "used", even if it doesn't have any noticeable effect. Much of the genome is non-coding, but those regions are just gibberish and would not result in a coherent protein were they to be transcribed.
Pretty much every gene in an organism's genome is "used", even if it doesn't have any noticeable effect. Much of the genome is non-coding, but those regions are just gibberish and would not result in a coherent protein were they to be transcribed.
12
I'm gonna talk about this on my science radio show! Soo cool to hear from all ya smart nerds... http://hollowearthradio.org/
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