Fashion in the animal kingdom, as beautiful and captivating as it may seem, can often be repetitive. There are only so many color schemes that can shout “Look at Me” among the grays and greens of foliage, muck, and other muck.
It should come as no surprise that animals use many of the same colors for different purposes.
A male northern cardinal’s brilliant crimson (Cardinalis cardinalisIn strawberry poison-dart Frogs, (Oophaga pumilioThis red flash is a strong warning to avoid it. Or you might inhale a deadly dose. Toxin.
Zachary Emberts, an evolutionary biologist at Oklahoma State University, and John Wiens, a colleague from the University of Arizona wondered how colors can evolve to serve different purposes in different animals.
The study included 1,824 land vertebrates. However, aquatic animals could be an entirely different story. Pot of fishThey classified their coloration into two categories: come-hither and get-lost. The common thread that connected each group was discovered.
Birds and lizards are the come-hither creatures that descend from diurnal or active during daylight ancestors. The nocturnal ancestral ancestors of the get-lost animal, such as snakes or amphibians are their descendents.
“Traits we see in species today can be a result their evolutionary history,” Emberts. “We were trying to find evolutionary patterns, so two separate analyses were done, one that used current day-night activity, and one that used ancestral day-night work.
They found no correlation between animal coloration and day-and-night activity. Instead, it is ancestral. It is a link that appears to be constant across all terrestrial vertebrates, which have evolved over 350 million years.
“It doesn’t matter how a species produces colors.” Wiens says. Although the way a bird makes red may be different from that of a lizard, this general pattern of day/night activity is still applicable.”
Researchers found that most of the ancestors of most of the animals they studied were quite plain and drab at the beginning. However, their vibrant colors evolved over time and most of them now live in environments where their bright colors are prominent. It is possible that brighter animals are more likely to survive and have their genetic material passed on to future generations.
The researchers analyzed colors including red, yellow, purple and blue. They found that all colors, except blue, were fairly evenly divided between sex signaling or warning. The reason could be sex signaling or warning.
“It’s fascinating to see that some colors, such as red, orange, or yellow, are used with similar frequency to both avoid predators as well as to attract mates.” Emberts.
“On the other hand, blue coloration was more often associated with mating than predator avoidance.”
It makes sense that diurnal animals have bright colors. Other animals, including potential mates, will be able to see them in daylight. While this may make them more vulnerable to predators, it makes them easier to spot and avoid. These females are more likely to be able hide from predators and raise their offspring.
However, nocturnal creatures slither around in the dark and snoop about. The male nocturnal serpent doesn’t need a bright color to signal his sexual desire if it isn’t visible by the females.
“Warning colors have evolved even among species that lack eyes.” Wiens says. “It’s not certain that most snakes or amphibians are able to see colors. Therefore, bright colors are usually used to signal predators to the species they belong to.”
Researchers suggest that the coloration evolved to warn diurnal predators about the sleeping animal, rather than to make it easier for them to avoid it. But future research may reveal more details. The team will continue to study the evolution of bright colours to determine if they have changed in function over time.
The research suggests that looking into the evolutionary history and animal traits could reveal patterns that may not be current today.
The research of the team has been published in Evolution.
