Mad Hops: It’s Grasshopper Season

Grasshoppers are intriguing creatures at any age. Owing to their size, ubiquity, and nonthreatening reputations, they are often the first insects a child will pick up. In school, grasshoppers are used as model organisms for teaching insect morphology and are often the first in a semester series of animal dissections. However, even with a lifetime of casual familiarity, many people have questions about grasshoppers. So, let’s jump in!

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The western horse lubber grasshopper (Taeniopoda eques) by Rhonda Spencer

What is a grasshopper?

Grasshoppers are common, wellknown insects in the order Orthoptera (straight-winged) and are characterized by the shape of their leathery wings and their powerful saltatorial (jumping) hind legs. They undergo simple metamorphosis (the juveniles look like mini versions of the adults) and have chewing mouthparts (as opposed to sponging or sucking mouthparts, which various insects have). Many grasshoppers are cryptic (exhibiting coloration serving to conceal them), although a few species display bright warning colors, especially on their hind wings, which they can pop out fanlike in a startling burst. Typically, females are larger than males; that is, they are sexually dimorphic.

What’s the difference between a locust and a grasshopper?

A locust is a migratory type of grasshopper that has the potential to swarm. Individually, grasshoppers can be relatively innocuous; however, given the right environmental conditions, a population will explode. Bright-green nymphs that feel the pressures of overcrowding undergo a chemical change in their brain. Production of serotonin increases, which makes them eat more, breed more readily, migrate, and on molting, change color to match the swarm. Locust swarms are notorious for their agricultural destruction (noted in biblical plagues), and some say they are the second most destructive insect to humans, after the mosquito.

What do grasshoppers eat?

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Yes, but what else?

Grasshoppers are mostly phytophagous; that is, they eat grass, leaves, roots, stems, flowers, seeds, and fruit. However, if they are lacking protein, several types (especially lubbers) are aggressively predaceous on insects and animals. Large numbers have even been observed congregating and happily devouring roadkill in southeastern Arizona.

Do they really spit tobacco?

When harassed, grasshoppers excrete digestive juices from their mouth as a defensive mechanism. The brown liquid substance, a mix of saliva and other gastric enzymes, may resemble tobacco spit. It’s acidic, distasteful, smelly, and can stain—a potent combination to dissuade predators from making a meal of the insects.

Why do they make noise?

Animals that make noise take the risk of being noticed by predators. A driving force that compensates for this danger is the chance to pass on genes. Males stridulate to simultaneously attract females and intimidate other males. By rubbing their hind legs across their forewing, grasshoppers produce a song, which they can amplify by stretching out their pleated wings. They hear by means of oval eardrums, called tympana, on the sides of their abdomen. Interestingly, grasshoppers are mostly diurnal (daytime) noisemakers, while crickets and katydids (who are also in the order Orthoptera), are nocturnal singers. These songs are crucial to successful courtship.

Some grasshoppers, like the banded- wing, make cracking or buzzing sounds when jumping. This is called crepitation. The noisy burst, paired with a flash of bright color on the hind wings, is startling to a predator. They land quickly, fold up the wings, and are immediately camouflaged in their surroundings—frustrating any bird or small mammal trying to catch a protein- rich meal, or an entomologist hoping to enlarge a collection.

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The rainbow grasshoppers (Dactylotum bicolor variegatum) by Howard Byrne

What’s the craziest grasshopper fact you know?

Grasshopper brains can be controlled by a worm! While eating vegetation, grasshoppers may ingest eggs of the parasitic horsehair worm. This worm hatches and feeds on the innards of the insects, changes their behavior, and ultimately drives them to seek water. The adult worm emerges from the drowned grasshopper, finds a mate, and lays eggs. A passing mammal (usually a cow, in Arizona) drinking from the water source will swallow worm eggs. After the eggs pass through the cow’s digestive system, they end up in poop on the grass, which is then eaten by a grasshopper, repeating the cycle.

When and where can I see grasshoppers in Tucson?

Tucson is temperate, and there’s rarely a season without some hoppers. However, the burst of activity is in the late summer, following the soaking from monsoon rains. In September the ecosystem is at its fullest. Tucsonans will often see horse lubbers (heavy bodied, mostly black insects), bandwinged grasshoppers (about 1 inch long and in everyone’s gravel driveway), and gray-bird locusts (the gray 2-inch-long insects eating through gardens). To see many species of grasshoppers in heavy numbers, head to the rolling grasslands of southern Arizona in late September. Every footfall of your hike will startle grasshoppers, and you will appear to be walking though popcorn.

Are they nature’s best jumpers?

Nick Johnson, former UA basketball player, had an impressive vertical jump of 47 inches. This distance pales in comparison with how far a grasshopper can travel in a single bound (20 times its body length!).

Each of a grasshopper’s back legs has an enlarged femur that is twice as long as the front and middle legs and contains a voluminous extensor muscle. The insect is able to travel such distances from the combination of force (large muscles) and speed.

However, the grasshopper is not as impressive as a flea, which can jump 150 times its own body length. Never underestimate the power of little things!

Written by Catherine Bartlett, Education Specialist 


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