Showing posts with label Cuvier. Show all posts
Showing posts with label Cuvier. Show all posts

May 13 - Remembering Georges Cuvier

    Posted on May 13, 2022

This is an update of my post published on May 13, 2011:




Georges Cuvier named the pterodactyl and the mosasaurus. He opposed the idea of evolution. He proved that species of animals have gone extinct. He believed that the “original people” were white (Caucasian). He established the fields of comparative anatomy and paleontology.


Like so many scientists who lived and worked a long time ago, Cuvier had some really good ideas that established or revolutionized branches of science—but he also had some ideas that, since his death, have been shown to be utterly wrong. 

(And racist!)

When you look at the work of Cuvier, a French biologist and paleontologist who died on this day in 1832, you can't help thinking - or at least hoping - that he would have changed many of his incorrect views if he could've seen the evidence we humans have gathered since his time.

For example, in opposing evolution—the idea that populations of animals change over time—Cuvier was opposing the theories of his contemporaries, Lamarck and Geoffroy Saint-Hilaire. And, we now know, those theories were incorrect. Charles Darwin's theories of common descent and of evolution driven by natural selection—which have been added to, now that we know about genes and DNA, and which TONS of evidence show are essentially correct—wouldn't be published until more than 20 years after Cuvier died.


Fossils drawn by Georges Cuvier

As the saying goes, in science we stand on the shoulders of giants. Today's average 11 year old kid knows more science than the most brilliant Ancient Greek natural philosopher, and a college freshman pre-med student knows more Bio, probably, than Cuvier! Still, Cuvier is one of those giants of intellect and endeavor upon whose work biology is built.


Cuvier believed in catastrophism...

Cuvier studied fossils of animals that no longer exist today, such as the wooly rhinoceros and the mammoth, and he came to believe that they went extinct due to some sort of natural catastrophe. Geologists who put forth the theory of catastrophism explained geological formations through catastrophes, too; for example, the carving of canyons and valleys might be explained by mighty floods.

The opposite of catastrophism is uniformitarianism. This is the theory that geological features can be explained by forces we can see today, acting gradually over years, decades, centuries, millennia. Under this theory, valleys and canyons (for example) are carved slowly and gradually by the slow movement of glaciers, or by many rainstorms and erosion events.


Glaciers carve U-shaped valleys.
Rivers tend to carve V-shaped valleys,
but of course over the course of time,
many of these valleys widen.




 
Today geology is based on uniformitarianism and catastrophism, together. Earthquakes and volcanoes seem like natural catastrophes to us, but to a geologist, these and other tectonic forces are constant enough to be an important, almost continuous, part of land formation and shaping. Erosion tends to be almost continuous, too. Catastrophes such as super-volcanoes, major storms and floods, and of course huge meteors (perhaps asteroids or comets) that impact the Earth all happen occasionally and sculpt the land as well. 

Biologists and geologists have worked out together that (almost certainly) at least some animal extinctions have been caused by huge tectonic or impact events. (And of course, extinctions of some species of plants and other organisms would share these same causes.)




April 4 - First Paleontological Lecture!

Posted on April 4, 2017

Even during ancient times, humans saw signs of much-more-ancient creatures that had once lived, but no longer existed.


Just as we do, ancient peoples once in a while found old fossilized bones or other fossils that would made them wonder about creatures who lived long, long ago. Finding a skull that looked like no living creature must have been fascinating to the ancients. We think that myths of cyclops and dragons, among other creatures, were influenced by these rare finds.

It wasn't until Georges Cuvier started to compare the bones and body structures of living creatures to those of fossils that the scientific study of ancient lifeforms began.

This branch of science is called paleontology, because paleo- means "old" or "ancient." (You probably already know that the -logy part of the word basically means "study of.")

Of course, we now call Cuvier the "Father of Paleontology."

(By the way, fossils don't include JUST bones. Any trace of a long-ago creature/organism can be a fossil - tracks or footprints, leaf impressions, seashells, petrified wood, fossilized nests, insects preserved in amber, fossilized teeth and eggs and bones and claws - even fossilized poop! - all are considered fossils.)



The comparison of organisms' body parts is called comparative anatomy, and before Cuvier comparative anatomy only dealt with modern creatures. Based on these comparisons, animals (and plants and other organisms) had, in the early 1700s, been grouped into different species, families, classes, and phyla. This classification system is called Linnaean taxonomy (because the basic structure and many of the classifications were created by a scientist named Carl Linnaeus). 

Starting in the late 1700s, Cuvier expanded Linnaean taxonomy to include extinct creatures that had left behind fossils. 

And on this date in 1796, Cuvier delivered the first lecture on his new science!





Also on this date:













Sonia Kovalevsky Mathematics High School Day (held on different dates by different institutions)




















Anniversary of the knighthood of Francis Drake







Check out my Pinterest boards for:
And here are my Pinterest boards for:

August 23, 2012 - Happy Birthday, Georges Cuvier


According to Wolfram Research, Cuvier's students dressed up in devil costumes and woke up their professor in the middle of the night. They chanted, “Cuvier, Cuvier, we have come to eat you!”

Apparently not the least bit fazed, Cuvier looked around at the “devils” and said, All animals with horns are herbivores. You cannot eat me.” Then he went back to sleep.

(I'm sure you know that herbivores are animals that eat only plants. Some examples of horned herbivores are rhinos, sheep, goats, bison, cattle, giraffes, muskox, antelopes.)

Georges Cuvier, born on this date in 1769, was a French zoologist (a scientist who studies animals). He helped to establish two new fields of study: comparative anatomy (studying the similarities and differences between body structures) and paleontology (the study of prehistoric life).

Cuvier had strong opinions on all sorts of biological and geological theories. For example, he thought that most fossils were mineralized bones of animals that no longer existed. Well, he was right—and this seems pretty obvious to us now, but in the late 1700s, many people believed that no species had ever gone extinct. Cuvier thought that the fossil record showed that animals didn't change and evolve over time—that new species suddenly appeared and just as suddenly (later) disappeared. He brought up the fact that mummified humans, ibises (a kind of bird), and cats are just like modern humans, ibises, and cats, and he said that that was evidence that animals don't evolve. A scientist named Lamarck shrugged away this point, pointing out that the Egyptian mummies Cuvier examined are only a few thousand years old, not hundreds of thousands of years old (or, we know now, millions of years old)—and, Lamarck argued, evolution happened too slowly to show much change after only a few thousand years. On this point, Cuvier was wrong and Lamarck was right. (But on other discussion points, Lamarck was wrong and Cuvier right!)

Other topics of inquiry during Cuvier's life include catastrophism (the idea that lifeforms are sometimes impacted and even driven to extinction by natural catastrophes), stratigraphy (the idea that older sedimentary rocks lay under younger sedimentary rock layers—which helps us figure out the relative age of fossils found inside those rocks), and the “correlation of parts” (the idea that the five bones in a bat's wing are related to the five fingers in a human hand, and so on).

It's interesting to me to see that scientists who are brilliant, knowledgeable—even ahead of their time—can still be very wrong about things. We can't judge ideas based only on how highly esteemed the person saying them is—we have to look for evidence, and sometimes we have to wait years for enough evidence. Eventually, data showed that some of Cuvier's ideas were right and that others of his ideas were wrong. (Just remember, though, if Cuvier had had the luxury of being born in the twentieth or twenty-first century, when soooooo much more is known about biology and sooooooooo many more fossils have been found and dug up, he would almost assuredly see eye-to-eye with today's scientists on these matters.)


Also on this date:



May 13, 2011 - Celebrating Georges Cuvier

Important Note: Blogger has been down for about a day, which is why yesterday's post disappeared for a while and today's post was hugely delayed. I am sure the programmers at Google worked hard to get it back up ASAP, and I am sorry that this post came out so late...

Georges Cuvier named the pterodactyl and the mosasaurus. He opposed the idea of evolution. He proved that species of animals have gone extinct. He believed that the “original people” were white (Caucasian). He established the fields of comparative anatomy and paleontology.


Like so many scientists who lived and worked a long time ago, Cuvier had some really good ideas that established or revolutionized branches of science—but he also had some ideas that, since his death, have been shown to be utterly wrong. When you look at the work of Cuvier, a French biologist and paleontologist who died on this day in 1832, you can't help thinking that he would have changed many of his incorrect views if he could've seen the evidence we humans have gathered since his time.

For example, in opposing evolution—the idea that populations of animals change over time—Cuvier was opposing the theories of his contemporaries, Lamarck and Geoffroy Saint-Hilaire. And, we now know, those theories were incorrect. Charles Darwin's theories of common descent and of evolution driven by natural selection—which have been added to, now that we know about genes and DNA, but which TONS of evidence show are essentially correct—wouldn't be published until more than 20 years after Cuvier died.

As the saying goes, in science we stand on the shoulders of giants. Today's average 11 year old kid knows more science than the most brilliant Ancient Greek natural philosopher, and a college freshman pre-med student knows more Bio, probably, than Cuvier! Still, Cuvier is one of those giants of intellect and endeavor upon whose work biology is built.


Cuvier believed in catastrophism...

Cuvier studied fossils of animals that no longer exist today, such as the wooly rhinoceros and the mammoth, and he came to believe that they went extinct due to some sort of natural catastrophe. Geologists who put forth the theory of catastrophism explained geological formations through catastrophes, too; for example, the carving of canyons and valleys might be explained by mighty floods.

The opposite of catastrophism is uniformitarianism. This is the theory that geological features can be explained by forces we can see today, acting gradually over years, decades, centuries, millennia. Under this theory, valleys and canyons (for example) are carved slowly and gradually by many rainstorms and erosion events.

Today geology is based on uniformitarianism and catastrophism, together. Earthquakes and volcanoes seem like natural catastrophes to us, but to a geologist, these and other tectonic forces are constant enough to be an important, almost continuous, part of land formation and shaping. Erosion tends to be almost continuous, too. Catastrophes such as super-volcanoes, major storms and floods, and of course huge meteors (perhaps asteroids or comets) that impact the Earth all happen occasionally and sculpt the land as well. Biologists and geologists have worked out together that (almost certainly) at least some animal extinctions have been caused by huge tectonic or impact events.