Within nature there are a variety of colors expressed by all sorts of organisms and objects. Among these organisms are ones that gleam with all the colors of the rainbow which they express through iridescence. Normally when looking at a colored object, the object will absorb and reflect rays of light. Depending on which rays of light are reflected, the color of the object will change. For example, an object reflecting blue light will appear blue because that is what is being sent to our eyes. Things with iridescence reflect light in a different manner. Iridescent things shimmer like the rainbow because there are very very small structures that alter the way light gets reflected. As a result, the light gets reflected differently depending on the angle and distance one is from the object that results in a rainbow of color. Iridescence is not exclusive to any animal group and shows itself in a variety of organisms.
The Blue Morpho is part of a large group of butterflies that are native to South America, Central America, and Mexico. Their iridescence is caused by tiny structures arranged in multiple layers on the tops of their wings. The full structural design of the coloration is very complex, so much so that humans have yet to be able to replicate the morpho’s colors. It is believed that the Blue Morpho uses its iridescence as a way to communicate with each other over long distances. It does this by reflecting a large amount of ultraviolet light (can’t be seen by humans). This allows the butterflies to recognize fellow morpho butterflies and in some species to discern between male and female.
The only iridescent mammal to ever be discovered, the Golden Mole is a small insectivore native to Southern Africa. Surprisingly they are unrelated to true moles and instead have achieved the “look” of the mole through convergent evolution. As an underground dwelling mammal, they have very strong front digging claws as well as fur that repels dirt and water. The Golden Mole usually will dig itself a permanent home about one meter beneath the earth. Its home consists of a variety of different rooms used for things such as storage, bathrooms, and a nursery. Since they rarely come to the surface the Golden Mole has adapted hyper efficient kidneys and almost never needs to drink water. In addition, the mole has adapted to listen for the vibrations of termite alarm calls allowing them to find food. Currently, eleven of the twenty-one species of Golden Mole are under the endangered status and conservation attempts are underway.
The Cuckoo Wasp is a very colorful, usually metallic looking, solitary insect that is widespread across the globe. It is known as a parasitoid, This means it uses another organism as a feed source for its growing young–so very similar to a parasite, but it kills its host. What makes these wasps unique besides their dazzling colors is the way it raises its young. In fact the Cuckoo Wasp does not raise its young at all, other wasps do. The way it manages this is by laying eggs into the hives of other solitary wasps. The young Cuckoo Wasp then consumes the other larvae within the hive as food. The host wasp will continue to bring food to the Cuckoo Wasp larvae completely unaware that it is a different type of wasp. Another odd behavior Cuckoo Wasps possess is the ability to curl up into a ball in a process known as conglobation. This ball shape looks extremely similar to a pill bugs (roly poly) defensive curl and offers the same protection.
This very tiny bird is only about 3 to 3 ½ inches long and is local to the coastal areas of California going down to Mexico. All Allens Hummingbirds are a colorful green on their back chests with rust colors on their sides. The males have a special patch of feathers under their head that is iridescent and usually colored orange or red. They use this patch to attract a female during their mating dance. The male unfurls its iridescent neck feathers and begins a series of quick back and forth flights in front of the female. He then begins flying in bigger arcs until he enters the final stage of the dance where he flies high into the sky and performs an audible high speed dive. Like all hummingbirds because of their high energy lifestyle they must feed every hour or so. These meals consist of plant nectar and any small insects that happen to be around the flower. Although they are very tiny birds they are incredibly protective of their territory. In fact they have been known to try and fight off even larger predatory birds such as kestrels or hawks.
This snake shimmers like a rainbow when exposed to light due to its highly iridescent scales. Much like the Blue Morpho, this rainbow glow is caused by tiny structures within the scales and the layering of the scales themselves. They are native to a variety of places in Southeast Asia such as China, Thailand and the Philippines. They are not venomous and kill their prey through constriction, mainly feeding on frogs, lizards and small rodents.
The Peacock is a commonly known iridescent bird that looks like it was designed by an artist, well at least the males do. Female peacocks are simple looking having only brown and grey feathers with no extravagant tail. The females have small tails that they use to intimidate other females and warn their young of danger. The reason the male is so overdressed is that he has to look as good as he can to attract a female. It is believed that the more eyespots the peacock has in his large tail feathers the more attractive he will be to a female. From a survival standpoint, more eyespots means looking like more animals in a dimly lit area and therefore greater survival aiding to the reproductive success of the species.
Green Bottle Fly
This shiny metallic green fly that gleams in the sunlight is located around the world, mainly in the western hemisphere. Bottle Flies are part of the blowfly family which means they lay their eggs on high protein sources such as rotting meat. Surprisingly humans have found a use for blowflies or more specifically their larvae. In medicine, their larvae, or maggots, are used to clean wounds of dead tissue and skin to prevent further infection and allow the wound to heal at a faster rate. In addition to medicine, criminal studies also use blowflies as a time marker for homicide cases. They do this by estimating the time of death based upon the development of the blowfly maggots.
This shiny metallic fish isn’t truly a shark, but a shark catfish. This sadly is simply a family of catfish and not a special shark catfish hybrid. The iridescent shark is native to Southeast Asia with most of them living in the Mekong Basin. They are generally omnivorous, usually feeding on plants, small fish, and crustaceans. Sizes range greatly, with the largest ones being capable of reaching a length of around four feet and a weight of about 97 pounds. Due to their shiny metallic look and the diversity of sizes, they are often kept as pets in an aquarium. They are also sold commercially as food which is called Swai. So I suppose having an iridescent shark as a pet can also serve as an emergency food ration.
The Violet Sabrewing is a very large hummingbird native to Central America all the way south to Costa Rica. On average, they are roughly 5.9 inches long making them the largest hummingbird found outside of South America. The adult males are mainly violet-blue with green on their backs while adult females have a violet throat with green above and gray below it. They feed exclusively on nectar and surprisingly they are not that aggressive which is unexpected due to being almost twice as big as the very aggressive Allens Hummingbird.
This highly iridescent and glossy beetle can be found around the world with around 15,000 different species discovered. Their sizes range from around 0.10 to 3 inches long and their exoskeletons are often used to make jewelry in areas such as India and Japan. The larvae of jewel beetles are all plant or wood boring insects of some fashion. Most will choose dead wood to bore into to feed and develop into adult beetles. Some species will only bore and develop in wood that has been burned recently and have some adaptations. These adaptations include infrared vision and the ability to sense pine wood smoke from up to 50 miles away.
The Paua Snail is more commonly known as an Abalone in the United States and is found around the world in shallow coastal waters. The Abalone itself is a large gastropod or snail that clings to a hard surface on the ocean floor with a muscular foot. This foot is also how it moves if it were to do so. The shell of the Abalone is truly what makes the organism special. Depending on the species, the shell can be highly iridescent and valuable, often containing mother of pearl material. The shell itself is made from microscopic layers of calcium carbonate held together by a special protein. When an impact hits the shell instead of shattering, the protein allows for the expansion of the calcium carbonate layers absorbing force. In fact, the shell is currently being researched to create stronger ceramic materials.