yego.me
💡 Stop wasting time. Read Youtube instead of watch. Download Chrome Extension

Fossils 101 | National Geographic


2m read
·Nov 11, 2024

(gentle music)

[Narrator] Like buried treasure, they lie hidden from sight. Echoes of an ancient past, they whisper secrets and tell tales once lost to time. Fossils are remnants or impressions of ancient organisms that are naturally preserved in stone. While there are hundreds of fossil types, they are often grouped into two major categories: body fossils, which are the preserved remains of plants and animals, and trace fossils, which are records of an animal's behavior, such as footprints. Together, they form the fossil record, a primary account that tells the story of life on Earth through stone.

Fossilization, or the process of preserving organisms in stone, can occur in countless ways. These methods are largely grouped depending on whether the organisms are altered during the fossilization process. Fossilization that does not alter a specimen can help to preserve its original form and texture. Among many methods, this group includes organisms that have been frozen, preserved in tar pits, and mummified. One special case involves trapping organisms, oftentimes insects, in amber. This process begins when an organism is covered in tree sap. The sap, or resin, forms a protective seal around the entrapped organism. Over time, the soft resin hardens and turns into amber with the organism suspended within. This process creates a biologically inert tomb for the organism, allowing its soft tissues to be remarkably preserved.

Other fossilization methods change the specimen as it is being preserved. For instance, carbonization transforms soft tissues into thin black films of carbon. In fact, countless layers of carbonized plant material create a well-known fossil fuel, coal. But one of the most common types of fossilization that changes a specimen is called permineralization. Permineralization begins when minerals from water or the ground enter the pores of dead plant or animal material. Over time, the minerals attach themselves, clinging onto cellular walls and building a crystalline network in the empty cavities. This mineralization hardens the bone and turns it into stone, thereby preserving its original structure in fossil form.

When conditions are right, fossilization can preserve crucial information about an organism. Permineralized wood often contains enough information to identify its tree genus and sometimes its species. Insects encased in amber have been so well preserved that their genetic material was extracted and partially sequenced. And footprints left behind by ancient hominids help paint a picture of what life was like for early human ancestors millions of years ago. With every fossil uncovered, the planet's ancient past becomes clearer, helping shape our understanding of our world today.

(gentle music)

More Articles

View All
Heisenberg's Uncertainty Principle Explained
Today I am doing an experiment that demonstrates Heisenberg’s Uncertainty Principle. So here, I have a green laser, and I am firing it down towards the front of the room through a narrow slit. Now, that slit can be adjusted so it can be made narrower or …
Safari Live - Day 376 | National Geographic
[Music] This program features live coverage of an African safari and may include animal kills and carcasses. Viewer discretion is advised. Good afternoon everyone! Well, no better way to start an afternoon game Drive than with the little prince, who’s po…
Everything you need to know about being a Real Estate Agent: The Real Estate Agent Academy
What’s up you guys, it’s Grant here. So, I put a lot of time, effort, and thought into making this video, and it would mean the world to me if you guys give it the chance to watch it all the way through. Plus, if you’re interested in becoming a real esta…
Ottoman, Safavid and Mughal Empires | World History | Khan Academy
We are now going to go further in our study of the evolution of the empires in Asia, and in this video, we’re going to focus on what happens in North India, Persia, the Middle East, and the Anatolian Peninsula, what we would consider modern-day Turkey. So…
Why Do We Love Sports?
Imagine you’ve been living in the trenches for weeks, maybe months. Corpses of your allies, friends, brothers surround you. The smell of their rot, revolting; the pain of your loss, excruciating. Rain water has made the ground where you stand thick with m…
How Do Cartels Get Their Weapons? | Trafficked with Mariana van Zeller
[engine revving] [suspenseful music] MARIANA VAN ZELLER: In my quest to expose how American guns are trafficked throughout Mexico, I never expected to be headed out to sea. But as we move deeper into the waters, these smugglers break down their operation…