Zoological Investigations

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Love ’em or hate ’em, insects are arguably the most important animals on earth. They are often viewed as the most successful animals on the planet, too. Many insects are essential for the continuation of life on earth (as we know it) through their roles as plant pollinators and as degraders of waste products left by other organisms, which prevents massive build-up of organic wastes that would otherwise bury the planet. In fact, about two-thirds of all flowering plants are pollinated by insects.

Insects are also among the most important carriers of and vectors for diseases that kill millions of humans and other economically important
mammals annually.

Insects are frequently used as models in scientific research — due to their (often) small size and rapid generation times, many can be bred quickly and in large numbers in laboratories for experimentation in various areas, including genetics and medicine.

Insects have been around for a long time, too — at least 400 million years. For comparison, the first mammals appeared roughly 225 million years ago. Man, are there lots of insects! Estimates vary, but it is thought that there are anywhere from six to 10 million living species of insects alive today, and these species are grouped into 29 different orders.

Beetles make up the order coleoptera. With over 360,000 described species, it is the largest order of insects in the world. In fact, at least 25 per cent of all species rambling about the planet today are beetles.

How will you know if you are looking at one of these wonderful, wildly abundant beetles or just some other type of insect? Beetles are perhaps most easily recognized by their two sets of wings. One set is the kind of wing you think of when you imagine insects flying (I’m sure you imagine insects flying quite often), while the other set of wings, called elytra, are hardened into a protective, leathery sort of cover that protects the more delicate wings underneath and may also act as aerofoils. The order coleoptera is amazingly diverse and contains both the largest and some of the smallest insects on the planet today. It is about one of the largest living insects that you, the enthralled reader, are going to learn — the Hercules beetle.

The Hercules beetle, Dynastes hercules, is a type of rhinoceros beetle (subfamily dynastinae) and is a member of the family scarabaeidae, the scarab beetles. These Hercs, as I’ll call them, are native to South and Central American rainforests, and the Lesser Antilles. They range from 50 to 170 milimetres (over six inches) in body length — making them one of the world’s largest beetles and the largest of the six beetles in the genus Dynastes.

As if their size weren’t impressive enough, male Hercs have two big horns that can be even longer than their body: one that comes from the lower (ventral) portion of the head curving upward, and another that comes from the thorax at the base of the upper (dorsal) region of the head curving downward, like pincers or pliers. When males fight, they try to pick one another up with their horns and slam them headfirst to the ground. Females lack horns.

Hercules beetles are not poisonous and do not attack humans. They mostly just hang out in leaf litter trying to survive the decimation of the rainforest and look really cool and menacing. They are herbivorous; the larvae eat rotting wood and dung while adults feed on decaying fruit and vegetable matter.

Again, just cleaning up the garbage. Really, they are humble civil servants of the rainforest, never complaining about their smelly job or asking for recognition, even though they deserve it. Hercs live for about 1.5 years, only three to four months of which are spent as adults. They are primarily nocturnal and are strongly attracted to light.

My favourite thing about Hercs is that if you correct for size, Hercules beetles are, proportionally, the strongest animals on the planet. They are able to lift up to 850 times their own body weight!