Researchers have found a clear link between the nose size of the male monkeys and the number of females in their harems
A new study says that proboscis monkeys that have large nose tend to attract more females.
It has long been assumed that proboscis monkeys with exaggerated male traits, such as a large nose, have great advantage over their counterparts when it comes to sexual relationships. However, there is no scientific evidence to back this theory. This is the first time researchers have found a clear link between the nose size of the male monkeys and the number of females in their harems.
"Although the unique nature of the 'odd-nosed' proboscis monkey has long been admired as an extremely attractive visual feature by biologists, explanations for its evolution have so far been gleaned more from folklore than from science,” said Dr. Sen Nathan, Assistant Director of Sabah Wildlife Department and Ph.D. student at Cardiff University.
"We show evidence supporting both male-male competition and female choice as causal factors in the evolution of enlarged male noses. We also observed that nasal enlargement modified the resonance properties of male vocalizations, which probably encode male quality. Our results therefore indicate that the audiovisual contributions of enlarged male noses serve as advertisements to females in their mate selection."
Proboscis monkeys are endemic to Borneo and only their males have long nose.
To better understand the purpose of enlarged nose, researchers carried out a study in the Lower Kinabatangan Wildlife Sanctuary and observed the behavior of free-ranging proboscis in the area. Researchers found that the size of the nose actually matters in mate selection.
"Based on the collected data, we tested the correlations between body mass, facial characteristics, testicular volume, vocalizations, and number of harem females in captive and free-ranging proboscis monkeys,’ said Dr. Ikki Matsuda, from Chubu University and Kyoto University in Japan.
"In addition to finding that enlarged male noses serve as advertisements to females in mate selection, we also found that males with larger noses also tended to have larger body mass and testis. This suggests that nose enlargement is a reliable predictor of social dominance and high sperm count."
RELATIVE TAGS: quokka, proboscis, red squirrel, endangered monkeys, probiotics monkey
SOURCE: I4UNEWS
