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Dinosaurs!
Jul. 25th, 2006 10:47 pmSunday we drove to Houston to visit the Houston Museum of Natural Science. Robin wanted to see the Body Worlds traveling exhibit.
You might think that is exactly the kind of thing I would also like to see. After all, my best friend and I actually made up a Girl Scout badge on human anatomy and physiology. (It had a bone going diagonally across the badge in one direction and a blood vessel in the other.)
But no. There's a difference between reading about something or seeing line drawings of something or seeing disembodied innards or being in a simulated tiny submarine inside a blood vessel and seeing actual dead, cut-open people with faces, fabulously preserved in some plastic kind of way.
I went to an exhibit on dinosaurs instead. A bit more has been learned about dinosaurs since I was in school. For example, in 1996, the first dinosaur fossils with feather imprints were found. Now it's thought that many, most, or even all dinosaurs had feathers or protofeathers (perhaps even with just the shaft of feathers).
So it is now assumed that feathers evolved first for warmth and then later were used to help with flight. And they think the way the first birds flew is different from how modern birds fly, but I couldn't tell how.
There was a big display on dinosaur locomotion. It's fun to make computer simulations based on scanned in bones. It's fun to see how modern day large birds (ostriches) move and how modern day really large land animals (elephants) move and then try to make educated guesses about dinosaurs.
It is actually impossible for adult elephants to develop big enough muscles to be able to run, if you define running as a gate where periodically all feet are off the ground at once. Younger elephants can run, though. It is expected that the same was true of the large dinosaurs. The young ones could run, but a grown Tyrannosaurus Rex, for example, could not, and could go no more than 10 to 25 miles per hour.
I learned that chickens are very fast. They have even larger muscles than they need for running. Chickens are built for speed! (Actually, I suspect they were bred for big drumsticks.)
I learned that people used to think that all the armor and plates and horns and things, like on a Stegosaurus' back, were for protection, but now they suspect a lot of it may have been to attract the attention of hot lovers, just like with modern day horned animals.
There was a display on the extinction. When I was in school, no one knew what caused it. Then I heard that it was decided that it was from a meteor because they actually found where the meteor hit. But this display said there were at least three interacting problems. One, which occurred before the meteor or comet hit, was the second largest (known) volcanic event in earth's history. No, they didn't say what the largest one was.
The layer of lava from that eruption is 1.25 miles thick. A smaller eruption (or set of eruptions) in modern times is thought to have led to "the year there was no summer" (1816).
There were also abnormalities in the weather. I couldn't figure out if there was something beyond how volcano eruptions and meteors affect the weather or not.
And that meteor was supposedly 6 miles in diameter. The ones that hit Jupiter recently maxed out at only 2 miles across.
So, 65 million years ago, all the "non-avian" dinosaurs went extinct. The others are what evolved into birds.
One interesting question was how, with so many things going on, half of all species survived. Another interesting thing is that there was an earlier extinction event that led to the extinction of 95 percent of all species.
You might think that is exactly the kind of thing I would also like to see. After all, my best friend and I actually made up a Girl Scout badge on human anatomy and physiology. (It had a bone going diagonally across the badge in one direction and a blood vessel in the other.)
But no. There's a difference between reading about something or seeing line drawings of something or seeing disembodied innards or being in a simulated tiny submarine inside a blood vessel and seeing actual dead, cut-open people with faces, fabulously preserved in some plastic kind of way.
I went to an exhibit on dinosaurs instead. A bit more has been learned about dinosaurs since I was in school. For example, in 1996, the first dinosaur fossils with feather imprints were found. Now it's thought that many, most, or even all dinosaurs had feathers or protofeathers (perhaps even with just the shaft of feathers).
So it is now assumed that feathers evolved first for warmth and then later were used to help with flight. And they think the way the first birds flew is different from how modern birds fly, but I couldn't tell how.
There was a big display on dinosaur locomotion. It's fun to make computer simulations based on scanned in bones. It's fun to see how modern day large birds (ostriches) move and how modern day really large land animals (elephants) move and then try to make educated guesses about dinosaurs.
It is actually impossible for adult elephants to develop big enough muscles to be able to run, if you define running as a gate where periodically all feet are off the ground at once. Younger elephants can run, though. It is expected that the same was true of the large dinosaurs. The young ones could run, but a grown Tyrannosaurus Rex, for example, could not, and could go no more than 10 to 25 miles per hour.
I learned that chickens are very fast. They have even larger muscles than they need for running. Chickens are built for speed! (Actually, I suspect they were bred for big drumsticks.)
I learned that people used to think that all the armor and plates and horns and things, like on a Stegosaurus' back, were for protection, but now they suspect a lot of it may have been to attract the attention of hot lovers, just like with modern day horned animals.
There was a display on the extinction. When I was in school, no one knew what caused it. Then I heard that it was decided that it was from a meteor because they actually found where the meteor hit. But this display said there were at least three interacting problems. One, which occurred before the meteor or comet hit, was the second largest (known) volcanic event in earth's history. No, they didn't say what the largest one was.
The layer of lava from that eruption is 1.25 miles thick. A smaller eruption (or set of eruptions) in modern times is thought to have led to "the year there was no summer" (1816).
There were also abnormalities in the weather. I couldn't figure out if there was something beyond how volcano eruptions and meteors affect the weather or not.
And that meteor was supposedly 6 miles in diameter. The ones that hit Jupiter recently maxed out at only 2 miles across.
So, 65 million years ago, all the "non-avian" dinosaurs went extinct. The others are what evolved into birds.
One interesting question was how, with so many things going on, half of all species survived. Another interesting thing is that there was an earlier extinction event that led to the extinction of 95 percent of all species.