Geissmann, T. (1990). Twinning frequency in catarrhine primates. Human Evolution 5: 387-396.
T. Geissmann
Anthropological Institute, University Zürich-Irchel, Switzerland
Key words: Twins; twinning frequency; multiple
births; primates; Catarrhini.
Abstract: It has been repeatedly suggested that twinning frequency in most
catarrhine primates is approximately the same as in humans, whereas the frequency
in the chimpanzee and the gorilla might be higher. This study presents a re-evaluation
of the evidence from the pertinent literature. It can be demonstrated that most data
on twinning frequency in Old World monkeys and apes should not be used because of
their small sample size. A lower limit of 1500 pregancies is suggested here. If all
frequency estimates taken from smaller samples are rejected, only four estimates
for Macaca mulatta and Papio hamadryas remain. The estimates range
from 0.19 to 0.35% and are in fact lower than the frequencies of most (but not necessarily
all) human populations. The published birth samples for apes are, however, relatively
small, and the resulting twinning rates may not be reliable.
Site by Thomas Geissmann.
For comments & suggestions, please email to
webmaster@gibbons.de
Gibbon Research Lab. Home: |
![]() |