In some recent discussions about hybrids and speciation (which I will not
comment further on) someone raised the idea of Notho eggs being transferred
from one temporary pool to the next by mud adhering to elephants (or birds
feet for that matter). I have already written about this and, basically,
said that I did not believe it to be a common process. Recently, I was
writing up a report and the subject matter was such as to remind me of a
good example that illustrates this unlikelihood, and which I thought some of
you might be interested in.
In the Kruger National Park in South Africa, there are two locations of
Nothobranchius. One includes both N. rachovii and N. orthonotus. The former
is of the "black" form of the species while the latter is a very strongly
red form with green flashes in the unpaired fins. This population of N.
orthonotus is, in my opinion, the most striking of all known populations of
At the second locality we find N. orthonotus only and it is a much less
attractive population, being very dull by comparison to the other
Now, these localities are only about 10 kilometers apart and they occur in
an area heavily frequented by elephants. I do not know the statistics but
the KNP must have one of the highest, if not the highest, population
densities of these animals of any area or park in Africa. In fact the high
population is a serious problem.
I have seen plenty of elephants in that part of the KNP where the Notho
locations are. So, that being the case, if Notho eggs could be easily
transported from one pool to another in mud caked on elephants, why do we
see the profound differences between the Nothobranchius populations of the
two locations. If that were a viable mechanism then we would expect that N.
rachovii would have been relatively easily introduced into the second
location as well and the N. orthonotus would not display such profound
differences in colour pattern. The one locality is, literally, just a few
kilometers down the road from the other.
Furthermore, if one considers the time factor, then it is obvious that there
has been plenty of time for such a transfer to take place. The localities
are associated with deposits that are about 2 million years old. The
habitats themselves would be a bit younger than this but probably not very
Brian R. Watters
University of Regina
Regina, Sask. S4S 0A2, Canada
Ph: (306) 584-9161 (home); (306) 585-4663 (work)
Fax: (306) 585-5433
E-mail: bwatters at sasktel_net
To join the AKA see http://www.aka.org/pages/join.html
Archives are at http://fins.actwin.com/killietalk/