My name's Katie, I work here at the Lapworth
Museum as Assistant Curator.
I'm here to talk to you today about a trilobite.
Trilobites lived 525 to 250 million years
ago.
Like all arthropods they had an exoskelton
made up of three distinct parts.
The cephalon, which is the head here, and
the segmented body which is the thorax and
the pygidium or tail.
So this was all to protect the soft body parts
which you can see here.
When trilobites first appeared in the rock
record in the earliest Cambrian they already
had this complex exoskeleton as well as the
world's first complex visual system.
They were very diverse and they had already
diversified over a wide range of environments
from shallow to deep water environments.
The trilobite I'm going to talk to you about
today is called Crotalocephalus.
It was found in the Anti Atlas in the Morocco
region and it's from the Devonian period so
it's actually 415-400 million years old.
As you can see it's got very well preserved
pygidium and pleural spines which you can
see just about here.
These would have been used to protect it from
predators as well as to stop it sinking into
the soft sediment.
So it's likely that it would have lived on
the sea floor and its glabella here, which
is on the cephalon, is likely to indicate
that it would have been a predator and it
would have collected prey.
Trilobites as a species lived for over 275
million years.
Over this time they did actually have a lot
of extinction events to contend with.
During the Devonian however their luck was
coming to an end and the group was actually
confined to just one order, which was the
Proetida.
So the order Proetida was restricted to shallow
shelf environments.
In the middle Permian unfortunately there
was a major regression, which is a sea level
fall, so this further restricted them to the
environment and they couldn't survive when
the end Permian mass extinction wiped out
95% of marine life so, unfortunately, the
trilobites came to an end.
