Video 4.7.5: Chemical Fossils - Prof. Phil Manning

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Del curso dictado por University of Manchester

Our Earth: Its Climate, History, and Processes

85 calificaciones

University of Manchester

Our Earth: Its Climate, History, and Processes

85 calificaciones

Develop a greater appreciation for how the air, water, land, and life formed and have interacted over the last 4.5 billion years.

De la lección

Life, and its Effect on Earth’s Climate System

Video 4.7.1: Devonian: From Fish to Tetrapod - Prof. Phil Manning7:07

Video 4.7.2: Carboniferous - Prof. Phil Manning2:57

Video 4.7.3: Jurassic Coast - Prof. Phil Manning3:47

Video 4.7.4: Dinosaurs - Prof. Phil Manning 4:23

Video 4.7.5: Chemical Fossils - Prof. Phil Manning 4:32

Conoce a los instructores

Prof. David M. Schultz
Professor of Synoptic Meteorology
School of Earth, Atmospheric and Environmental Sciences
Dr Rochelle Taylor
Postdoctoral Research Associate
School of Earth, Atmospheric & Environmental Sciences
Dr Jonathan Fairman
Postdoctoral Research Associate
School of Earth, Atmospheric and Environmental Sciences

Our understanding of the evolution of birds has come a long way since the first

fossil remains in the Solnhofen Limestone back in 1861.

There have been remarkable deposits found especially in Asia more specifically,

in Liaoning province in China.

Here, we see another snapshot of

the evolution of birds some 125 million years ago.

As we build up a better and better picture through amazing fossil remains,

we can begin to understand this beautiful tapestry which is the evolution of birds

on our planet today.

When you look at the fossil remains of Archaeopteryx, if it wasn't for

the feathers, you could easily be forgiven for

identifying this as a predatory dinosaur.

You can see the socketed teeth in the skull.

You can see the long bony tail, and

the overall body plan of the animal is that of a predatory dinosaur.

But when you look a little bit closer, you see that the bones are hollow.

Again, a predatory dinosaur character, but something that we see in birds also.

Then we see the fused clavicle, the wishbone.

Very avian character, very birdlike.

But here in the exceptional preservational circumstances that we only find

in places like the Solnhofen Limestone in Bavaria.

We see feathers.

This remarkable adaptation allows this animal to break it's

bonds with the earth and have flight.

The exquisite remains of Confuciusornis are preserved in a very different

environment to that of what we see with the Solnhofen Limestone and Archaeopteryx.

For in Liaoning province, where we find Confuciusornis.

They're freshwater lake deposits, which are fine-grained,

interbedded mudstones with ash deposits.

These are volcanic ash deposits.

And probably belie the cause behind so many of these animals

littering these lake deposits, and finding these exceptionally preserved fossils.

Archaeopteryx has many characters that we'd expect to see in a bird, but

there's some which we don't really want to see in a modern bird.

The last time you saw a chicken, it didn't have teeth.

The concept of killer chickens from hell is not one we'd like to really entertain

because birds have evolved beaks.

One of the first beaked birds that we find in the fossil record is that

of Confuciusornis from Liaoning province in China.

These beautiful fossils, preserved in what is a volcanic ash deposit,

lay down in the lake, some 125 million years ago.

The fossil remains are beautiful.

And they look very much like a modern bird.

What is most remarkable about these fossils, is the feathers are so

exquisitely preserved.

We have even been able to map the chemistry of pigments.

So we can for the first time understand what these creatures might have

actually looked like some 125 million years ago.

All life on earth is diagnosed by specific chemistry.

Each tissue type in your body has its own elemental building blocks that we can

pull apart using some of the most powerful light in the universe, synchrotron light.

At such particle accelerator sources,

we can generate intense x-rays that excite the very atoms that compose a fossil.

And tell us exactly what they're composed of.

Sometimes, these atoms tell a fantastic tale.

One of lost pigments and forgotten lakes.

In the case of Confuciusornis, we're able to look at the pigmentation preserved

in discrete chemical building blocks of new melanin which is

characterized by central ziggurats of copper.

And we were the first group anywhere on the planet to identify this discrete

chemistry that's associated with the pigmentation of an animal,

some 125 million years old.

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