Charles Darwin was that famous
white-bearded scientist who went on a
dangerous voyage around the world on the
HMS Beagle. On this trip he collected a
ship load o' data in the form of plants
and animal specimens. Darwin then used
these specimens to think about his
theory of evolution by natural selection.
This box, called a Vasculum, went with
Darwin on that daring voyage and was
used to protect delicate plants
collected in the field. The vasculum
played an important role in maintaining
and preserving the physical
characteristics of the plant such as
petal arrangements and allowed Darwin to
investigate these characteristics later
in greater detail within a more
practical environment like his study and
not a boat!
My name is Alex Munro I'm a
botanist and a fellow of the Linnean
Society. By collecting data on the form and
shape of plants and on DNA, we can use
that to compare how related they are to
each other. That will enable us to create a hypotheses about how they evolved.
The Galapagos Archipelago, a series of
volcanic islands, is home to a variety of
prickly pear cacti. These cacti are
eaten by tortoises who have pretty
hearty appetites. Tall variety of the
prickly pear cacti grow on islands
with giant tortoises
whereas shorter varieties grow on
islands with no tortoises. When Darwin
compared the leaves of the cacti he'd
collected from the Galapagos with leaves
of the cacti he'd collected from South
America
he noticed they were both paddle shaped
so must be closely related. Darwin
theorized that the plants in the
Galapagos must have been transported to
the island as seeds via wind, water or carried
by an animal, maybe on its fur, feathers
or in its faeces. Because of the islands
distance from the mainland
these plants then became isolated and,
over a long period of time, evolved to be
much taller than their mainland
relatives so they could avoid being
eaten by those savage, prickly pear-obsessed tortoises.
The reason it's important to collect plants is that we
share this planet with about 350,000
species of them, and yet for the vast
majority we know very little. By
collecting them in the field, we can start to
understand how they help maintain the
living world around us.
The living things that Darwin collected formed the data on
which he was able to formulate his
theory of evolution by natural selection.
Powerful theories such as these still
depend on the collation of large amounts
of data and so the importance of
collecting plants is still crucial today.
