Color vision drove primates to develop red skin and hair, study finds

May 24, 2007

You might call it a tale of "monkey see, monkey do." Researchers at Ohio University have found that after primates evolved the ability to see red, they began to develop red and orange skin and hair.

Humans, apes and Old World monkeys, such as macaques and leaf monkeys, all have trichromatic vision, which allows these primates to distinguish between blue, green and red colors. Primatologists have disagreed about whether this type of color vision initially evolved to help early primates forage for ripe fruit and young, red leaves among green foliage or evolved to help them select mates.

Now a new study published online this week in American Naturalist by Ohio University researchers Andre Fernandez and Molly Morris rules out an initial advantage for mating and suggests that red-color vision evolved for non-social purposes, possibly foraging. But once developed, trichromaticism drove the evolution of red skin and hair through sexual selection.

Fernandez, the study's lead author, first began to question the strict correlation of food choice and color vision while studying howler monkeys in Costa Rica. He recently compiled data on the color vision, social and sexual habits and red skin and pelage of 203 different primate species.

The researchers then used a phylogenetic tree representing the evolutionary relationships among all the primate species under study to test hypotheses about the order in which the traits of red color vision, gregariousness (highly social behavior) and red coloring evolved. By comparing the traits of individual species in this evolutionary context, Fernandez and Morris could statistically deduce the probability of their ancestors having the same traits, as well if any of the traits were correlated with one another.

They found that the species that could discern red and orange hues were more likely to develop red and orange skin and hair, as well as highly social habits that make it easier to visually compare mates. In fact, the more social the trichromats are, the more red coloring they show.

"Neuroscience research has found some evidence of a perceptual bias for more brilliant colors," said Fernandez, an Ohio University doctoral student. "So, it is reasonable for primates with trichromatic color vision to respond more when they see bright colors."

So while foraging may have initially sparked red color vision, the new ability was likely "recruited" for social purposes.

"It looks like red skin and hair became a sexual preference," said Morris, a fish biologist who studies how physical traits such as coloring evolve through sexual selection. "So while the benefits in terms of eating may not apply anymore, the (red-color) vision in some groups is now relevant in social terms."

Source: Ohio University

Explore further: Compact wool measurement tool may find home on the range

add to favorites email to friend print save as pdf

Related Stories

Extrasolar storms: How's the weather way out there?

Jan 13, 2015

Orbiting the Earth 353 miles above the ground, the Hubble Space Telescope silently pivots toward its new target. At the same time, flying 93 million miles away in interplanetary space, NASA's Spitzer Space ...

TV viewing support for color-blind emerges with Eyeteq

Dec 04, 2014

UK-based Spectral Edge has made its technology available for set-top TV boxes so that viewers who are color-blind can differentiate shades alongside viewers who are not color-blind. Eyeteq is the name of ...

Four Kansas laboratories work on ending famine

Nov 13, 2014

Can a wasp feed the world? It can help. If its larvae are nurtured near millet fields where a devastating moth steals harvests from the field, they can grow to become predators that destroy the pests and save a crop. And ...

Recommended for you

Population genomics unveil seahorse domain

5 hours ago

In a finding vital to effective species management, a team including City College of New York biologists has determined that the lined seahorse (Hippocampus erectus) is more a permanent resident of the we ...

Researchers develop new potato cultivar

8 hours ago

Dakota Ruby is the name of a new potato cultivar developed by the NDSU potato breeding project and released by the North Dakota Agricultural Experiment Station. Dakota Ruby has bright red skin, stores well and is intended ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.