Cicada versus Locust
Someone asked me what the difference is between a cicada and a locust. Initially I was surprised by the question, as I have always seen them to be two completely different species of insects, however, it seems that many people refer to cicadas as locusts.
Since there is obviously some question about what a Locust is let's first settle that. A locust is a type of grasshopper, more specifically, a locust is a short horned grasshopper. A long horned grasshopper is known as a katydid or, more commonly, just a grasshopper.
In parts of Australia, and the USA, cicadas are often known as locusts, however, a cicada is an entirely different type of insect than the locust or the grasshopper. The cicada is related to the aphid and comes in two varieties; the annual and the periodical cicada. The annual cicada has a lifecycle which repeats annually, i.e. they breed and hatch once per year. The periodical cicada may have either a 17 or 13 year lifecycle and spend the time between breeding buried in the ground until billions of individuals hatch in unison. This gives rise to the name thirteen year locust and seventeen year locust.
The confusion over what a cicada is seems due to the possibility that when Christians settled in the Americas the periodical emergence of billions of large ravenous vegetation eating chirping insects drew parallels with the biblical stories about plagues of locusts and consequently the cicadas were referred to as locusts. The periodical cicada uses the "safety in numbers" survival strategy and each brood hatches in such large numbers that they simply cannot all be eaten by predators so it is easy to understand how people viewed their appearance as a plague.
Rather than attempting to explain the difference between a cicada and a locust I will direct you to glance at a couple of cicada pictures:
Books about cicadas on amazon
Images of cicadas on flickr
Images of cicadas on google images
Then contrast those images with a couple of locust pictures:
Books about locusts on amazon
Images of locusts on flickr
images of locusts on google images
Did you know that some people call cicadas locusts?
I hope that that was as fascinating for you as it was for me, if you have any comments please let me know and if you have any other questions which you'd like me to answer for free please send them to Ben Dash at firstname.lastname@example.org