History of paleontology

The history of paleontology is about learning about life on Earth by studying fossils from long ago. Paleontology helps us understand both living things and our planet. Long ago, smart thinkers like Xenophanes, Herodotus, Eratosthenes, and Strabo saw fossils of sea creatures and wondered what they meant. In China, people thought these fossils were dragon bones. During the Middle Ages, scientists like Ibn Sina tried to figure out how fossils were made.

In the Age of Reason, people started to study fossils more closely. By the late 1700s, Georges Cuvier showed that some species had completely disappeared, which we call extinction. This helped paleontology become a real science. In 1822, someone used the word “paleontology” for the first time, and after that, many scientists began searching for and studying fossils.

The 1800s were an exciting time for paleontology, especially after Charles Darwin wrote about evolution in 1859. Scientists wanted to learn how animals changed over time, including human evolution. In the late 1800s and during the 1900s, explorers found many important fossils all over the world. These discoveries helped us understand how different animals are related and taught us about big events that changed life on Earth, like mass extinctions and the sudden appearance of many animal forms during the Cambrian explosion.

Prior to the 17th century

Long ago, people found strange rocks that looked like creatures that once lived. The Greek philosopher Xenophanes of Colophon (570–480 BC) saw that some fossil shells looked like shells of sea animals. This helped him understand that places now on land used to be underwater a very long time ago.

Later, Leonardo da Vinci (1452–1519) also studied these fossils. He looked at animal remains and marks left behind, like holes and tracks. He used these clues to show that fossils came from real living things and that the rocks containing them were formed from layers of mud and sand from the sea. His ideas helped people understand the history of life on Earth better.

17th century

During the Age of Reason, scientists started looking at fossils more closely. In 1665, Athanasius Kircher thought big bones came from large ancient humans. The same year, Robert Hooke wrote about what he saw through a microscope in Micrographia. He compared petrified wood to normal wood and suggested fossils were once living things that changed over time. Hooke thought fossils were important clues about Earth's past.

In 1667, Nicholas Steno studied a shark and realized that some fossils called "tongue stones" were actually shark teeth. He studied rock layers and found that fossils were remains of living things buried in sediment. Even though he believed Earth was young, Steno thought the Biblical flood might explain why sea fossils were found far from the ocean. Other scientists, like Martin Lister and John Ray, were still unsure if some fossils came from living things, especially if they didn’t look like any animals known today.

18th century

In 1778, Georges Buffon wrote about fossils, like those of elephants found in cold places, to show that Earth used to be warmer.

Later, in 1796, Georges Cuvier compared bones of living elephants to fossils of mammoths and mastodon. He showed that these were different from modern elephants and were no longer alive. He also studied a huge fossil from Paraguay, naming it Megatherium, and found it was a giant sloth.

William Smith used fossils to match layers of rock in different places, making the first geological map of England. He discovered that each layer of rock had its own set of fossils, which came in a certain order. Around the same time, Cuvier and Alexandre Brongniart did similar work near Paris.

Early to mid-19th century

The study of fossils helped scientists learn about Earth's history. In 1812, a book by Georges Cuvier started the field of vertebrate paleontology. Later, the word "paleontology" was made to describe the study of ancient life through fossils.

During this time, scientists found many fossils of old reptiles and mammals. For example, Mary Anning found important fossils of sea reptiles in England. These discoveries showed that Earth had times when different kinds of animals lived. Scientists also began to make a timeline for Earth's history, splitting it into different ages using the fossils they found.

Late 19th century

Evolution

See also: History of evolutionary thought

Charles Darwin’s book On the Origin of Species, published in 1859, changed how scientists think about life on Earth. Fossils were very important to Darwin’s ideas. He was especially interested in fossils he found in South America during his trip on the voyage of the Beagle. These fossils showed animals like giant armadillos and giant sloths.

After Darwin’s book came out, scientists searched for more fossils. In 1861, scientists found the first fossil of Archaeopteryx in Germany. This animal had features of both reptiles and birds. In the United States, another scientist found fossils of early horses, showing how they changed over time.

Developments in North America

The second half of the 19th century saw paleontology grow quickly in North America. In 1858, a scientist described the first North American dinosaur, Hadrosaurus, from good fossils. The building of railroads and settlements after the American Civil War led to more fossil discoveries in places like Kansas. These finds helped scientists learn about ancient seas that once covered parts of the United States and uncovered many new dinosaur species, including Allosaurus, Stegosaurus, and Triceratops. Much of this work happened because of a strong competition between two scientists, Othniel Marsh and Edward Cope, known as the Bone Wars.

Overview of developments in the 20th century

Two big ideas in Earth science changed how scientists study ancient life. The first was radiometric dating, which helped scientists learn how old fossils are. The second was plate tectonics, which explained why fossils of the same animals could be found far apart on Earth.

During the 20th century, scientists searched for fossils all over the world, not just in Europe and North America. They found many new dinosaur species, especially in South America, Africa, and China. In China, fossils helped scientists understand how dinosaurs changed into birds and how the first animals with a backbone appeared. Scientists also studied times when many kinds of animals disappeared suddenly, called mass extinction events. One idea from 1980 suggested that an asteroid impact ended the time of the dinosaurs, known as the Cretaceous–Paleogene extinction event. Other studies looked at patterns in these extinctions over time.

New fossil discoveries showed how animals changed over millions of years. Finds in Greenland helped explain how fish changed into animals that could walk on land. Fossils in Pakistan showed how whales changed from land animals. In Africa, fossils helped trace human ancestors through time. By combining fossil evidence with studies of genes, scientists built family trees showing how different animals are related.

The 20th century also brought exciting discoveries about very early life. Before 1950, scientists did not have clear proof of life before the Cambrian period. But in the 1950s and later, they found tiny fossils of bacteria and other simple life forms, showing that life on Earth began at least 3.5 billion years ago.