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Language: en
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next up biogeography well biogeography
is the study of how animals plants and
other organisms have come to occupy the
places on the globe that they do imagine
a new island being born in the middle of
the ocean at first it's a hunk of rock
lifeless but gradually seeds and insects
and small animals originating from
nearby land masses get blown over on the
winds they come crashing ashore pushed
by the waves not all the organisms make
it but those that do with time adapt to
Island living perhaps even evolving into
new species just take birds there are
the finches of the galopagos islands the
birds of paradise of Papa new guini the
honey creepers of Hawaii and so on in
each case a single Island species
Diversified into an array of species
found nowhere else on Earth
biogeographies also got something to say
about why some closely related species
flourish on different continents it
seems odd until you recall that Earth
didn't always look this way a few
hundred million years ago all land was
part of Pangia a hulking supercontinent
there were no vast oceans to interfere
with the movements of organisms but then
starting about 170 million years ago the
continents drifted like vast rafts
across the sea and the species living
along the edges they were split in two
fast forward to the present day and you
get a plant in South America whose close
relatives grow in the tropical Pacific
we can use philogenetic trees as sort of
maps to help us reconstruct the
movements of organisms across the
planet