Scientists like a working holiday. Under the auspices of scientific
research I managed to make it as far afield as Singapore, New Zealand, and
Manchester. Charles Darwin made it to the Galapagos Islands. Alfred Russell
Wallace reached the Malay Archipelago, a catch-all term relating predominantly
to modern day Indonesia.
From Singapore over 60 individual
trips Wallace investigated the flora and fauna of some of the thousand plus
islands making up the archipelago. It was the 1850s, so travel wasn’t easy, but
in doing so Wallace independently theorised the principle of evolution.
The modern waterways around Singapore, about where Wallace would have
arrived
Wallace’s extensive
investigations led him to realise animals on the western islands (islands like
Sumatra and Java) came from a region of ‘oriental’ origin, while islands
further east (like New Guinea) were home to animals from ‘Australian’ origin.
As a result species like the tree kangaroo can be seen struggling about the
trees of Australia and New Guinea, but not on islands further west than a deep
oceanic channel now called the Wallace Line.
Wallace’s 60 trips (in red) took him all around the Malay archipelago
The Wallace Line separates two
biogeographic regions. Intriguingly the channel separating the islands – Bali
and Lombok – is only 35 km wide, roughly the length of the channel tunnel. But
it is the depth of the channel which is important. Its depth ensured a barrier
between migration of land animals and birds even when sea-levels were
significantly lower, when islands as far apart as Australia and New Guinea were
united with land bridges.
So next time you think a
scientist is on a jolly, they probably are, but leave them be just in case.