As the content
from the OpenUp! project gradually grows on the Europeana portal, we are
preparing selections of natural history content highlights for you.
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| This specimen is stored at Botanic Garden and Botanical Museum Berlin-Dahlem and the image is under the Creative Commons cc-by-sa 3.0 license. More information about the image use is under this link http://bit.ly/P4KfFs. |
Our first object is an interesting poisonous plant: Abrus precatorius. This herb commonly
named Jequirity or Crab's Eye is widely distributed in the tropics today,
mostly as an invasive weed. It is a perennial climbing legume up to 10 m high,
with white to red coloured flowers and pinnate leaves. The leaves are consumed
as a vegetable in central and east Africa. Well known are the bright red seeds
with black top, used as beads for necklaces and other jewellery, as well as in
percussion instruments. Due to the uniform weight of the seeds - nearly exactly
0,28 g - the seeds were also used for weighing gold and jewellery. The seeds
contain a strong toxin, named abrin. Abrin inactivates protein synthesis in
cells. A fatal dose of this poison is only 3 micrograms (µg), therefore one
seed can be lethal for a human. In traditional medicine in Asia and Africa the
purified and detoxified seeds are a medicine against diseases of the eye.
This displayed specimen is a so-called
isotype of a special subspecies of Abrus
precatorius which occurs in Africa, as the name of the subspecies, subsp. africanus, suggests.
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| Abrus precatorius specimen on Europeana portal http://bit.ly/NsyukG. |
A type specimen is of outstanding value
for the biologist: The scientific description of an organism is generally done for
one individual of the species (or subspecies), which is usually prepared and
stored in a natural history museum with international status. The scientific
name is closely linked with this individual, called a holotype. In the case of
our Abrus precatorius subsp. Africanus specimen, we received from the
Kew herbarium a duplicate of the holotype, called an isotype.
More objects are coming, stay tuned!
