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First living things on land clarification

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First living things on land clarification : First living things on land clarification (This video copyrighted under Create Commons Attribution and Share-Alike CC-BY-SA license)

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In the video on the Cambrian explosion
I talked about how suprisingly, or somewhat surprisingly
animals were the first to colonize
or to move on land.
They did that before plants did.
And someone brought up a question which I thought was a very good question.
If they were the first, what did they eat?
I thought it was a good question
and it justified a video on clarifying
exactly who was first on the land.
So right here, this is a picture of algae on the coast
this is kind of algal scum right here.
So this is algae.
And just to be clear
sometimes cyanobacteria, which we talked about as the first
photosynthetic organism
Sometimes that's called blue-green algae
but that's really bacteria.
Algae is considered eukaryotic
it just doesn't have the structures of modern plants.
So this is algae right here.
And our best estimate
is that algae actually colonized coastal rocks
about 1.2 billion years ago.
G for "Giga".
So if you wanted the first thing that even resembled
or was close to plants or animals
and if you consider algae close to a plant,
then this would be the winner of who got on land first.
Now in the last video where I talk about animals
colonizing the land first
they weren't animals that only existed on land.
They were animals that probably spent
most of their time in the ocean collecting food or whatever
and they would show up on land to lay eggs.
And if you think about it, back then
the land would have been a really good place to lay eggs
because there wouldn't have been much else on the land.
So you would have been protected from predators.
So it might have been slug-like creatures like this
Some people talk about spider-like creatures
but it still would have been at the coast.
And these would have been creatures that spent a lot of time
in the ocean
and some time on land.
So this is what I was referring to
as kind of animals colonizing land before plants.
And this would have happened about 530 million years ago.
Now the first living organisms to fully live on the land
their whole life is on the land
those would be plants.
So it depends if you think about things that live part of their lives
on land, you'd get the animals
things that live their whole life on land, then you'd get the plants.
So this right here, this is what we think
the first primitive plants would have looked like.
And the evidence, we actually don't have fossils of the plants themselves
we have fossils of their spores.
But we think that these, the earliest fossils of their spores, that shows that these existed
were about 475 million years ago.
So 1.2 billion years ago you have the algae
530 million years ago we have evidence
of things kind of oozing out of the ocean and maybe laying their eggs
475 million years ago we have evidence
of what we would call "really" plants
but the evidence is really the fossils of their spores.
And then the first evidence of what you could call
real 'animals' that have spent their entire life on the land
the oldest fossil we have was discovered in Scotland fairly recently in 2004
and it was...
this is the fossil over here, it was discovered by a bus rider, Mike Newman
it was a bus driver in Scotland, and they actually named the thing after him.
It is called Newmati,they got the Numati from Mike Newman
and this fossil is 428 million years old
428 million old
and right now it is the oldest fossil we have of a true land animals
if we think about true land animals
if you think about true plant versus true land animals that spend their entire life on the land
if you think about about things that spend part of their time on the land, then the animals probably would

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First living things on land clarification

First living things on land clarification : First living things on land clarification (This video copyrighted under Create Commons Attribution and Share-Alike CC-BY-SA license)