Posted on 12/13/2015 9:12:47 PM PST by Utilizer
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.
"This is one of the most comprehensive studies that attempts to date when these evolutionary divergences happened," says Luis Chiappe, a vertebrate paleontologist at the Natural History Museum of Los Angeles County in California, who wasn't involved in the new research.
Modern birds, a group called Neornithes (a name that combines neo and a variant of ornis, the Greek words for "new" and "bird," respectively) are the most diverse and widespread vertebrates on Earth today. Previous studies that used only information from genetic analyses of current species have suggested that birds arose anywhere from 72 million to 170 million years ago. But the new study, which includes anatomical data extinct species preserved in the fossil record, narrows that window considerably, says Joel Cracraft, an ornithologist at the American Museum of Natural History in New York City.
(Excerpt) Read more at news.sciencemag.org ...
After that, there's nothing but to reign in the remains of the old bird, if I care to ever attempt unleash it (to unleash an it it must first been upon a leash, wot?) upon unsuspected (I thought u was innocent!) passer-by again.
Not that there's much left of the thing now, it having been torn like the bear who tried to take on the pet wolverine who's quite difficult to get a leash on, tried that once (never again --don't ask).
Max got in through a hole he made in the brute's undercarriage, smuggled himself north-bound, dug like making a burrow arriving at the bear's cheese, then stole it all grin included. I'm not certain, but he I think he just kept right on making his escape out the other side. Deciding upon direction he should take, Max simply won't allow himself dissuaded.
If there be no recovery now for it (we'll have to give it time wait and see) I may need contact a Troy (Choot 'Em) Landy to see if there could be market for it.
You wouldn't have his number on you, by any chance?
very good
(imagine this an applause animation)
but where did that chicken come from?
The other side of the road.
But why did the chicken cross the road?
And the answer to that question is: uh, let's move along here...What's the next question...
He was blown across...From the impact of the asteroid...
The asteroid impact catapulted the dinosaurs into the air so they had to learn to fly - quickly?
After the asteroid crash 65 or 66 million years ago, also known as K-T boundry there must have been one huge ozone hole. The creatures that survived generally were small, probably lived in dens (like mammals), under embankments, (crocodiles), in trees and underbrush, like birds, or had protective shells like turtles, or feathers like birds. Thus they did not die of severe sunburn as probably did those big and small dinosaurs that had skin.
In other more primitive mass die-offs the geological record indicates newly formed (life-form) structural patterns above those other layers differing significantly enough than from fossils below to indicate changes beyond within previously existing life structures/body plan/frames.
Or so we've been told by the likes of mr. Gould, if memory serves.
The idea of gradual evolution versus sudden change is relatively new. The recent (last 100 years) discoveries regarding plate tectonics, and giant space bombs has changed thinking. Species can go along for many thousands of years with very few useful mutations and thus few changes. But if conditions are suddenly/catastrophically changed, then rapid evolution can take place. Just looking at the evolution on the Galopagus Islands with different subspecies on each island shows that. Also, what may look very rapid when examining fossils might take many generations. For example, I have read that it takes about 10,000 years of deposition for 1 inch of sedimentary rock to form. If some birds breed after 2 years, then that would be 5,000 generations of bird fossils possible in 1 inch of stone. By the same calculation, if a human generation is 25 years, then it there would be 125,000 years of evolution represented by 5,000 generations. This puts us back in Neanderthal territory, with archaic sapiens in the mix. I believe the “punctuated” part refers to the gradual evolution having an exclamation point thrown at it with fast changing conditions and fast evolution to go with it.
The punctuation mark in punctuated equilibria is the diastrophe (no joke) -- it's a semantic ploy to avoid the term "catastrophe". Most of the time there's stasis, other than loss of half of the genetic material of each parent (in species that use sexual reproduction and are not hermaphroditic); mutations are evidently irrelevant, since long sequences of the code is identical from person to person.
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