Submitted by Sarah Mileikis
A selective mating experiment by a curious butterfly breeder has led scientists to a deeper understanding of how butterfly wing color is created and evolves. The study, led by scientists at University of California, Berkeley, and the Marine Biological Laboratory, Woods Hole, is published in eLife.
When the biologists happened upon the breeder’s buckeye butterflies–which normally are brown–sporting brilliant blue wings through selective mating, they jumped on the chance to explore what caused the change in color of the tiny, overlapping scales that produce the wing’s color mosaic and pattern. They found that buckeyes and other Junonia species can create a rainbow of structural colors simply by tuning the thickness of the wing scale’s bottom layer (the lamina), which creates iridescent colors in the same way a soap bubble does. (Watch Video).
15 Types of Abalone – Characteristics
Abalones are marine snails that live in oceans, shores or rocky parts of the sea. Different species of abalones reside in different parts of the earth. Abalones are known for their colourful shells and flesh. https://deepoceanfacts.com/types-of-abalone
Factors for Decline
The primary factors contributing to the decline of green abalone are overharvest, suspected illegal harvest, and trade. Other factors include disease (withering syndrome) and elevated water temperatures (e.g., due to El Niño, warm water events). https://www.fisheries.noaa.gov/species/green-abalone
Animals which appear to shimmer and shine may have evolved these qualities as a way to startle predators, new research suggests.
Iridescent animals, such as kingfishers, peacocks and dragonflies, can produce a mesmerising display of colour depending on the angle of illumination or observation.
However, until now there has been limited scientific understanding of the function of iridescence and why this quality, known as ‘interference colouration’, has evolved independently several times in insects such as beetles and butterflies.
In a new study, published in the scientific journal Biology Letters, Dr Thomas Pike, a behavioural and sensory ecologist at the University of Lincoln, UK, suggests that for some organisms, iridescence evolved as a way to confuse predators. By producing startling changes in colour and brightness, the animal is able to briefly surprise a potential predator, increasing its chance of escape.
For the first time, Dr Pike tested whether interference colouration decreases the chance of predation. The experiment presented Japanese quail with a selection of virtual insects on a touchscreen.
https://phys.org/news/2015-04-iridescent-animals-startle-predators.html
Iridescence Helps Animals Evade Predators.
Iridescent creatures — such as dragonflies, catfish and boa constrictors — often dazzle onlookers with their shimmering colors. These alluring, luminescent hues may be key to an animal’s survival, helping it to confuse and escape from predators looking for a meal, a new study finds.
Iridescence is hardly the only conspicuous coloration that befuddles predators, said the study’s author, Thomas Pike, a behavioral and sensory ecologist at the University of Lincoln in the United Kingdom.
For instance, contrasting stripes may help animals escape from predators, likely because stripes make it hard for predators to judge speed and movement, Pike said.
The results suggest that changes in color or brightness, also known as “interference coloration,” may make it difficult for predators to track prey, Pike said. Many animals have iridescence, including some insects, like beetles and butterflies; birds; fish; reptiles; cephalopods, such as squid; and at least one mammal, the golden mole, he said.
“My findings suggest that significant anti-predator benefits may indeed be gained by having interference coloration, and may explain why interference colors are so widespread,” Pike said. “More generally, this raises the intriguing possibility that changing appearance may be important in predator avoidance, and that interference colors are a special case of this phenomenon.”
“It struck me that the conspicuous colors displayed by iridescent animals may also allow them to evade predators using a similar mechanism,” he said in a statement. [See Dazzling Photos of Iridescent Animals]
To investigate, he trained seven female Japanese quails to peck at a virtual black bug, represented by a 0.8-inch-diameter (20 millimeters) circle moving across a touch screen. When the quails pecked within 0.4 inches (10 mm) of the circle’s center, Pike rewarded them with dried mealworms.
Once the quails were proficient, he began mixing in iridescent circles. During each trial, each quail encountered 20 circles. Half of the circles were black and half of them were iridescent, and they were presented in a random order. The quails pecked, on average, fewer than three times in order to skewer a black circle. But the iridescent circles required an extra peck, on average, Pike found.
https://www.livescience.com/50616-iridescent-animals-confuse-predators.html
Iridescent Wild Turkeys. https://talesfromthewilds.blogspot.com/2014/03/iridescent-wild-turkeys.html
UNIVERSE 