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Asteroid Impact Helped Create the Birds We Know Today (sciencemag.org)
sciencehabit writes: Every bird alive today can trace its ancestry to creatures that lived about 95 million years ago on a chunk of land that split off from the supercontinent Gondwana, a new study suggests. The new family tree, compiled using information from fossils and from genetic analyses of modern birds, also reveals that this lineage underwent a major burst of evolution after an asteroid slammed into Earth about 66 million years ago and killed off the rest of their dinosaurian kin.
We know that the dinosaur group filled most of the world's ecological niches, and when the Chicxulub event happened, a vast number of niches had their occupants wiped out. All we need do is assume that for any species, there is a reasonably constant mutation rate, and most mutants won't survive when there are better-adapted competitors already in a given ecological niche. If the mutant can find a different niche, though, then its chance of survival goes up a lot. So, no need to assume a "burst of evolution" when the simpler explanation is a "burst of opened opportunities", thanks to all those wiped-out competitors.
So if i read this correctly
1.Asteroid hit earth
2.Dinos get blasted into the air
3.?
4.Some dinos learn to fly
So it's the fault of that asteroid that I have to listen to that damned mocking bird all night?
I thought it was commonly referred to as roughly 65 million years ago. Have we finally reached the point where it rounds up to 66 million?
According to the article "future birds" populated western West Gondwana and didn't spread until the dinosaurs died out. In other words they would not have moved in 30 million years and then suddenly they spread wildly when the dinosaurs vanished. Looking at how animals spread today and in recent history, it looks like they spread unless there is something preventing them from spreading, such as oceans or mountains. There is no reason to think it was any different back then and either they could walk/fly around to spread or they couldn't. There could be plenty of reasons why no fossils is found in an area even though the animal existed in that area. One could be that they haven't been found, another could be that past events prevented them from being created/preserved. Lack of evidence of existence is not evidence of lack of existence.
If "birds" existed in a greater area in low numbers and haven't been found, then the evolution explosion could be explained by multiple already existing birds growing rapidly in numbers and suddenly started to appear in the fossil records. They "cheated" and started their evolution earlier than we can detect, means the rapid appearing new diverse species was more of a growth in numbers than in species.
Sure this is pure speculation, but I think the same goes for the version provided in the article. I never understood why it is assumed when something is found, it's the earliest or latest member of the species to have ever lived. Most likely neither would be the case, which mean the timeframe of species will have to be open ended, yet if you look up a species, you get a closed ended timeframe based on the age of found fossils. I don't think it can be any different (we have to write what we know, not what we assume), but we should always remember the disclaimer that no fossils is not proof of non existence, both in age and geographical location. If it was, then some species would die out and then suddenly revive themselves 2 million years later.
I knew my bird was angry about something, I just never cared enough about her to find out what it was.
I thought it was commonly referred to as roughly 65 million years ago. Have we finally reached the point where it rounds up to 66 million?
That was a million years ago. You just sit and watch news day after day and suddenly the time passes without you noticing.
It is my understanding that everyone had heard...
Yeah, it was last Thursday.
systemd is Roko's Basilisk.
Was there a giant obelisk involved?
If you want news from today, you have to come back tomorrow.
I can confirm this. We passed the 65.5 million year point so now we are rounding up.(It's really 65.5 millon years 3days 23 hours 6 minutes and 31 seconds.)
Why did the birds survive and not the dinosaurs? I'm guessing there were also dinosaurs living on that chunk of land?
I thought the most widely accepted theory about the dinosaur die off was that the meteor impact hurled debris into outer space which then reentered the atmosphere around the global, briefly superheating the air, which caused all the vegetation to flash burn. Any animals not in the water or safely underground would have died.
God created everything 6 thousand years ago. Watch kent hovinds movies.
If something has trouble to be explained - throw in an explosion.
Religion is what happens when nature strikes and groupthink goes wrong.
Everyone knows what a dinosaur is. Everyone knows what a bird is. Calling birds dinosaurs does nothing but sow unnecessary confusion. We can acknowledge that the two are very closely related (hey, even super-closely related) and still keep calling them by their different, well-known names so as to keep the conversation clear. I mean really, do you do around saying "non-human apes" every time you talk about apes? No, because that pedantry just makes conversation more difficult.
I think some people just need the romance of feeling they are living among T. rex's kin, so they keep driving the point home. Enough already.