I'm
Linda Holland. I'm a research biologist
in the marine biology research division
of Scripps Institution of Oceanography,
which is part of the University of
California San Diego.
People often ask me what is amphioxus
and why is it interesting to study.
Amphioxus is a small
marine animal that lives burrowed in the sand.
It looks like a little fish, but it has
no paired eyes,
no ears, no limbs,
just a little bit of a fan.
Someone said to me once gee these don't
look like much up, but it's important
because it's on the direct line to
the vertebrates
and so it's a very key phylogenetic organism
and it occupies this place right at the base
of the lineage leading to the vertebrates. Now the vertebrate and amphioxus
lineages
split about 520 million years ago during
the Cambrian
and there are fossils in the soft
mudstone of China of very
early, clearly vertebrates that look very
much
like a modern amphioxus. There are also
some fossils
of questionable, but maybe
fossil amphioxus. So this little organism
has not changed very much since the
Cambridge and it's this slow evolution
and its relationship to the vertebrates
that
makes it very important for
understanding
how humans, how we, came from our
invertebrate ancestors.
And so the amphioxus genome sequence was
done
by the amphioxus community
about 30 laboratories worldwide and the
key
take-home message from this genome
sequence
is that the amphioxus and human genomes
are very much alike.
 
