You may be surprised to learn that butterflies first appeared before flowering plants about 200 million years ago. With a lineage so long, these beautiful animals are full of surprises.
1. Butterflies’ wings follow two distinct color forms.
These forms, called pigment and structural, can be found alone or in combination on a butterfly’s wings. True to its name, pigment colors tend to be bright and inky, remaining definite regardless of the amount of light present. Structural colors tend to shift with the light, producing a “rainbow” or iridescent effect. An example of structurally colored wings can be found on the morpho butterfly.
2. Only about 4% of the world’s species of butterflies are found in the US.
Despite the 17,500 species of butterflies that currently exist, only about 750 of those live in the US, with the most abundant being the cabbage white butterfly.
3. Butterflies have more to them than meets (our) eye.
Did you know that butterflies can see colors that we cannot? This is because they can perceive ultraviolet light, which is outside the scope of our visual capabilities. Additionally, many butterflies’ wings include these “unknown” ultraviolet colors to attract mates.
4. Butterflies perform mimicry to better protect themselves from predators.
Take a look at the photo of a monarch butterfly below—now look again, because it’s actually the cunning viceroy butterfly posing as a monarch! It was originally thought that, like other wild animals who perform mimicry, viceroy butterflies “transform” into monarchs for protection against predators (the monarch’s bright colors indicate that it is toxic to birds, a common predator). However, viceroys are also naturally toxic, so this mutual mimicry ultimately proves beneficial to both species of butterflies.
5. Butterflies drink… turtle tears?
An incredible video of butterflies in the Peruvian Amazon shows them drinking the tears of turtles. Although it sounds like something out of a fairytale, butterflies actually have a practical reason for this behavior: sodium. Because butterflies cannot obtain sodium from their usual diet of floral nectar, they must search for sodium elsewhere; this could be in feces, dirt, and yes—turtle tears.
6. Butterflies’ pollinating capabilities are even more crucial to ecosystems than you may think.
We know that bees are excellent pollinators, but butterflies are pretty impressive sidekicks. This is partly because butterflies pollinate cotton flowers, a part of the cotton plant that bees naturally do not frequent, thus boosting cotton harvest. This type of pollination—where multiple insects work to pollinate different portions of the same plant—is called pollination complementarity, and it occurs with other plants too, like almonds.
7. Most adult butterflies only live for 1-2 weeks.
The life span of an adult butterfly is particularly short, but the growth process beforehand can be much longer. Comprised of four stages: egg, larva (caterpillar), pupa (chrysalis), and finally adult butterfly, the complete life cycle of a butterfly from egg to adulthood can last anywhere from 30 days to multiple years.
8. Monarch butterflies migrate as far as 3,000 miles.
Signaled by the cooler weather and shorter days, monarch butterflies from the northern US and Canada begin their journey towards Mexico in search of warmer weather. Alternatively, monarchs from across the western region of the US migrate to the coast of California for the winter and then once again scatter amongst other western states when spring arrives.
9. Butterflies, among other wild animals, are harmed by factory farming.
When new factory farms are built, large swaths of land—butterflies’ habitats and food sources—are destroyed. This land is used to grow corn and soy to feed farmed animals. Further, a toxic pesticide applied to these crops, called glyphosate, is upsetting monarch butterflies’ migratory patterns and driving them toward extinction. This past winter, only 1,914 monarchs were recorded overwintering on the California coast — the lowest number ever recorded, down from 30,000 last year and 1.2 million just two decades ago.
More Fascinating Facts About Butterflies
Butterfly Wings Are Transparent
How can that be? We know butterflies as perhaps the most colorful, vibrant insects around! Well, a butterfly’s wings are covered by thousands of tiny scales, and these scales reflect light in different colors. But underneath all of those scales, a butterfly wing is actually formed by layers of chitin—the same protein that makes up an insect’s exoskeleton. These layers are so thin you can see right through them. As a butterfly ages, scales fall off the wings, leaving spots of transparency where the chitin layer is exposed.
Butterflies Taste With Their Feet
Butterflies have taste receptors on their feet to help them find their host plants and locate food. A female butterfly lands on different plants, drumming the leaves with her feet until the plant releases its juices. Spines on the back of her legs have chemoreceptors that detect the right match of plant chemicals. When she identifies the right plant, she lays her eggs. A butterfly of any biological sex will also step on its food, using organs that sense dissolved sugars to taste food sources like fermenting fruit.
Butterflies Live on an All-Liquid Diet
Speaking of butterflies eating, adult butterflies can only feed on liquids—usually nectar. Their mouthparts are modified to enable them to drink, but they can’t chew solids. A proboscis, which functions as a drinking straw, stays curled up under the butterfly’s chin until it finds a source of nectar or other liquid nutrition. The long, tubular structure then unfurls and sips up a meal. A few species of butterflies feed on sap, and some even resort to sipping from carrion. No matter the meal, they suck it up a straw.
A Butterfly Must Assemble Its Own Proboscis—Quickly
A butterfly that can’t drink nectar is doomed. One of its first jobs as an adult butterfly is to assemble its mouthparts. When a new adult emerges from the pupal case or chrysalis, its mouth is in two pieces. Using palpi located adjacent to the proboscis, the butterfly begins working the two parts together to form a single, tubular proboscis. You may see a newly emerged butterfly curling and uncurling the proboscis over and over, testing it out.
Butterflies Drink From Mud Puddles
A butterfly cannot live on sugar alone; it needs minerals, too. To supplement its diet of nectar, a butterfly will occasionally sip from mud puddles, which are rich in minerals and salts. This behavior, called puddling, occurs more often in male butterflies, which incorporate the minerals into their sperm. These nutrients are then transferred to the female during mating and help improve the viability of her eggs.
Butterflies Can’t Fly If They’re Cold
Butterflies need an ideal body temperature of about 85 degrees Fahrenheit to fly.1 Since they’re cold-blooded animals, they can’t regulate their own body temperatures. As a result, the surrounding air temperature has a big impact on their ability to function. If the air temperature falls below 55 degrees Fahrenheit, butterflies are rendered immobile—unable to flee from predators or feed.
When air temperatures range between 82 and 100 degrees Fahrenheit, butterflies can fly with ease.3 Cooler days require a butterfly to warm up its flight muscles, either by shivering or basking in the sun.
A Newly Emerged Butterfly Can’t Fly
Inside the chrysalis, a developing butterfly waits to emerge with its wings collapsed around its body. When it finally breaks free of the pupal case, it greets the world with tiny, shriveled wings. The butterfly must immediately pump body fluid through its wing veins to expand them. Once its wings reach their full size, the butterfly must rest for a few hours to allow its body to dry and harden before it can take its first flight.
Butterflies Often Live Just a Few Weeks
Once it emerges from its chrysalis as an adult, a butterfly has only two to four short weeks to live, in most cases. During that time, it focuses all its energy on two tasks: eating and mating. Some of the smallest butterflies, the blues, may only survive a few days. However, butterflies that overwinter as adults, like monarchs and mourning cloaks, can live as long as nine months.
Butterflies Are Nearsighted but Can See Colors
Within about 10–12 feet, butterfly eyesight is quite good.4 Anything beyond that distance gets a little blurry, though.
Despite that, butterflies can see not just some of the colors that we can see, but also a range of ultraviolet colors that are invisible to the human eye. The butterflies themselves may even have ultraviolet markings on their wings to help them identify one another and locate potential mates. Flowers, too, display ultraviolet markings that act as traffic signals to incoming pollinators like butterflies.
Butterflies Employ Tricks to Avoid Being Eaten
Butterflies rank pretty low on the food chain, with lots of hungry predators happy to make a meal of them. Therefore, they need some defense mechanisms. Some butterflies fold their wings to blend into the background, using camouflage to render themselves all but invisible to predators. Others try the opposite strategy, wearing vibrant colors and patterns that boldly announce their presence. Bright colored insects often pack a toxic punch if eaten, so predators learn to avoid them.