Episode 4 - The Giraffe
Veterinary scientist Mark Evans acts as guide as a team of
experts investigate the inner workings of the giraffe.
Creationists question how this extraordinary creature could
have evolved such a long neck, but for Professor Richard Dawkins the anatomy of
the world's tallest animal provides some of the best arguments in favour of
Darwinian natural selection.
For example, one nerve takes a huge detour up and down the
long neck, from the voice box to the brain, via the chest - hardly the work of
an `Intelligent Designer'. And, despite its length, the neck still only has
seven vertebrae - the same number as almost all mammals, from mice to humans
and whales.
It’s huge heart must pump blood at high pressure around a
towering body, and it has evolved thick skin that acts as a natural 'G-suit'
coupled with a complex circulation system to avoid passing out when raising and
lowering its head.
And as the dissection team piece together the remarkable
evolutionary story of the giraffe, biologist Simon Watt observes them in the
field as they eat, forage and fight.