The animal was already well
known by native peoples throughout sub-Saharan Africa as a source of protein and
an aphrodisiac or fertility medicine (Kobel et al., 1996). Ease of maintenance
and breeding with injected hormone, has made X. laevis the standard
laboratory amphibian since the 1940's (Gurdon, 1996). Being aquatic
throughout their life Xenopus are easy to keep and are resistant against
disease and infection. Although crude, the use of X. laevis as an assay
for luteinising hormone, and thus pregnancy testing, led to mass movement of the
humble Platanna to laboratories pan-globally. Subsequent use of X. laevis
as the laboratory amphibian in schools, universities, pregnancy clinics, medical
research establishments, and as pets, has meant that this animal is familiar to
biologists the world over, and has even established feral
populations. 
A recent
review of diet in Xenopus reinforced these observations of reliance on
aquatic invertebrates and cannibalism, based on the gut contents of several
species in native and feral habitats (Tinsley et al., 1996). However, recent
studies of behavioural feeding mechanisms have shown this aquatic frog to be
proficient at catching prey out of water with very fast striking movements
(around 10 m s-1) which
minimise the risk of attack by predators and maximise the chances of capturing
prey with rapid escape reflexes. This movement is faster than any other
previously recorded for Xenopus (Measey,
1998). The mechanism explains the presence of some of the terrestrial components
in the diet of Xenopus, although it seems likely that there are other
mechanisms through which terrestrial prey may be acquired. John Measey,
1998 
Department
of Zoology
University of the Western Cape
Private Bag X17
Bellville
7535
Cape Town
South Africa
Tel: 021 - 959 2261
Fax: 021 - 959 2312