Transcript:

Today on Animal Fact Files we’re talking about cicadas. Thank you to friendly bullet for today’s request!

Probably the quintessential sound of summer, cicadas are some amazing arthropods. Not only can these insects reach sizes of more than two inches (5 centimeters), they can also produce sounds that may be heard more than a mile away. And each cicada species has its own unique call. There are almost 3,000 described cicada species and it’s believed there are hundreds more to be discovered! Cicadas are most diverse in tropical areas, but they can be found worldwide... well, except for Antarctica. Though cicadas are generally found over a wide range, separate species often don’t have a large range of distribution. Cicada species are typically confined to one specific area, such as a forest, desert, or grassland, and this is usually because they're tied to a host plant species.

Adult cicadas suck up plant juices - they even eat fruits! These adults are often mistakenly called locusts, but really the two arthropods aren’t related. Locusts are grasshoppers; cicadas aren’t even capable of jumping! Heck, they’re not even that good at walking if we’re being honest. Cicadas get around using flight. Technically locusts fly, too, so there are some similarities, however locusts can be detrimental to crops while cicadas are mostly harmless to plants. In large quantities, cicadas can harm young, weak plants that aren’t strong enough to bear the weight of many cicadas, but other than this cicadas don’t have the destructive power locusts have! They’re just harmless, noisy derps.

Large quantities of cicadas aren’t unheard of. Specifically in North America big groups of cicadas will emerge at roughly the same time during certain years. These are called periodic cicadas, and they only emerge from the ground every 13 or 17 years! These are the longest lived cicadas. Other cicada species are called annual cicadas, though this name can be a bit misleading.

The reason cicadas call is to attract mates. In nearly all cicada species only the males are able to produce sounds - there are, however, two species found only in australia in which females produce sounds, as well - but they’re a little different and we’ll talk about them in just a bit. Males may be sedentary and call females to him - these are usually the loudest cicadas - or they may fly around in search of a female. When they find each other, they mate and the female lays her fertilized eggs. Typically these are laid in woody plant material, like a tree trunk, but sometimes they are also laid grass - it just depends on the species. Inside the eggs, cicada nymphs develop. The nymphs emerge from the eggs, fall to the ground and burrow in with their claws, and find a nice plant root to suck for the next few years. This is why the term “annual” is a bit misleading. Technically, adults of these species’ do appear annually, but the nymphs take a few years to develop - so they end up being more than a year old when they emerge. When nymphs emerge from the ground a few years later, they shed their exoskeletons, become adults, and leave behind the iconic cicada shells.

The two weird cicada species we mentioned earlier communicate using vibrations not through the air, but through plants. These cicadas spend most of their time as adults hidden under bark throughout the day, and come out at night to search for a mate. For the other thousands of cicada species, the sounds they produce are heard via an ear like organ in their abdomen. These organs are sensitive to sounds from further distances, but don’t necessarily allow a cicada to hear any better than another insect.

As adults, cicadas don’t live more than a few months. They may be eaten by mammals, birds, reptiles. They’re also taken by cicada killer wasps and when they are they come to quite the unfortunate end.

For more facts on cicadas, check out the links in the description. Give a thumbs up if you learned something new today, and thank you for watching Animal Fact Files.