INSECTS -THE LITTLE SUPERHEROES

10,000,000,000,000,000,000

10 quintillions, this gigantic figure represents the total population of insects flying, swimming, slithering, creeping, or crawling across the Earth’s surface, each one serving a critical role. It translates to almost 1.2 billion insects per person.  There are more than 1.5 million known insect species, more than three times the total of other animals on the planet.

Even if their look repels us, a world without them would be uninhabitable. Insects are the unsung heroes of the ecosystem, and they need to be acknowledged.

But as per the findings, more than 40% of bug species are dwindling, with a third facing extinction. Insects have an extinction rate eight times higher than mammals, birds, and reptiles. Insects’ overall mass is decreasing at a rate of 2.5 percent every year, hinting that they may go extinct within a century.

What if all of the World’s insects simply vanished? 

The results would be dire & catastrophic.

It would be a summer without singing cicadas and shimmering fireflies are over, and grocery stores with empty shelves. There will be no humming bees to pollinate apple, cherry, peach, or almond trees. Without pollination from mother nature’s bustling pollinators, harvests, flowers, and plants would be unable to generate seeds. The fields would be devastated.

Insects are crucial due to their diversity, ecological relevance, and impact on agriculture, health impacts, and natural assets. Insects provide the biological foundation for all terrestrial ecosystems. They recycle nutrients, pollinate plants, disseminate seeds, maintain soil structure and fertility, regulate other species’ populations, and serve as the primary food source for others.

They play a vital role in the food chain, providing a direct food source for a variety of species, including humans. Insects enjoy an infinite variety of meals. Plants, fungus, animal carcasses, dead bodies, decomposing organic detritus, and practically everything else they stumble upon in their environment are all devoured by these insects.

Nobody likes those obnoxious, crippling cockroaches, but without them, the entire ecosystem would collapse. With approximately 4400 identified species, they are widely distributed all over the world. But, These despised cockroaches are protein-rich meals for birds, rodents, and even people, in certain parts of the globe.

There are over 3,000 mosquito species, all of which feed birds, bats, frogs, and other creatures. Without mosquitoes, the Creatures that feed on them would famish.

Caterpillars and grasshoppers nibble plant leaves, aphids and planthoppers suck off the plant fluids, honeybees collect pollen and imbibe nectar, while beetles and flies eat the fruits. The larvae of wood-boring bugs devour the wood.

There are over 350,000 beetle species, and many of them, notably dung beetles, are thought to be dwindling. Without the dung beetle, one of the Planet’s top recyclers, the planet would face the worst feces problem. Nitrogen-rich poop could stack up, suffocating vegetation and hindering fresh growth. Earth would be a nasty mess without those little heroes.

Farms, forests, and wilderness would all crumble, leaving a trail of dead. That’s where flesh-eating beetles and other corpse-eating insects come into play. They feast on dead flesh until only bones are left. Insects have a critical role as primary and secondary decomposers. Without insects to efficiently decompose and eliminate waste, dead plants and animals would pile up, making things very messy.

Insects overlooked for their relevance in the food web serve as the primary food source for many amphibians, reptiles, birds, and mammals. Land-dwelling birds like purple martins, barn swallows, vireos, warblers, ickers, whippoorwills, and swifts rely predominantly on insects to survive. Insects like beetle grubs, termites, and honeybees, are often consumed as a source of nourishment.

The silkworm, Bombyx mori, is the only source of commercial silk. The scale insects Datylopius coccus (Dactylopiidae) endemic to Mexico and Kermes vermilio (Kermidae) endemic to Europe provide red cochineal dye for fabrics and cosmetics. Bees produce honey.

Laccifer lacca (Lacciferidae), native to India, secrete shellac (a resin) used to make phonograph records and varnish. Salt cleaned by brine shrimp tastes better than salt that still contains the organism that the brine shrimp devour.

Parasites and predators, the bulk of which are insects, play a key role in maintaining the natural equilibrium. Many parasitic and predatory insects feed on plants or other insects or animals, or even humans. These insects are vital to keeping the pest population (insects or plants) in check.

Despite their many pleasant aspects, some insects can pose problems. Like the Arthropods, which spread various diseases like- malaria, yellow fever, dengue, West Nile virus, Lyme disease, ehrlichiosis, tularemia, Q fever, Colorado tick fever, Rocky Mountain spotted fever, plague, typhus, etc.

But it’s crucial to keep in mind that the good done by a vast variety of critical insects significantly surpasses any harm done by a few species.

HYMENOPTERA

Classification

Kingdom: Animalia 

  Phylum : Arthropoda 

    Class: Insecta (Endopterygota) 

      Sub-class : Pterygota 

         Order:Hymnoptera 

Hymenoptera

Hymenoptera means membrane wings. 

One of the largest insect order. 

Size range – 0.21nm(0.008inch)-5cm(2inch) in length. 

Usually 4 membranous wings

  • Forewing and hindwing are held together by small hook. 
  • Hind pair smaller than front pair

Complete metamorphosis (Holometabolous).

Mouthparts modified for chewing and sucking

In some form especially bees, certain Mouthparts (labium and maxillae) form a structure for sucking liquid food. 

Antennae usually with 10 or more segment. 

Larvae usually maggot like(i.e. Leg less) 

Large compound eyes, usually 3 simple eyes(ocelli) present. 

Females typically have a special ovipositor for inserting eggs into host or places that are otherwise inaccessible.

Most have constriction between the first 2 segment of the abdomen which is known as a wasp waist. 

Worldwide there are over 100,000 species included in the Hymenoptera. 

In Australia, there are about 1275 ant, 10,000 wasp, 2000 bee and 176 sawfly species.

Habitat

Found in all terrestrial habitat throughout Australia. 

May occur in soil, leaf litter and range of vegetation types especially flowers. 

Life Cycle

Some female produce young one without mating, while other can store sperms and spread out their egg laying to coincide with available food. 

Most species lay their egg to the host plant or paralysed food sources they have gathered into specially constructed nest. 

The Larvae will moult several times before they pupate.

Development may range from a few weeks for some parasitoid to much longer in social species. 

Feeding Habit

Feed on a wide range of foods depending on the species. 

Adult wasp mostly feed on nectar and honeydew. 

Some species are predator or parasites and spend their time searching out invertebrate hosts to lay their eggs on. 

Some are predator, scavenger, omnivores, seedeaters, fungus feeders or honeydew feeders

Suborder of hymenoptera :

1)  Symphyta(sawflies and horntails) 

2)Apocrita(ants, bees and wasps) 

Symphyta :(sawflies)

Most primitive Hymenoptera 

Have a broad junction between thorax and abdomen. 

Body has no waist. 

Paraphyletic group 

Females have a saw-like egg laying device for cutting slits in plants into which eggs are laid. 

Larvae are caterpillar-like and feed on outside and inside of plant tissue.

There are one or two parasitic families

lack of constriction at the base of the abdomen

 fly-like appearance and more extensive wing venation. 

They are often confused with lepidopteron larvae but it include–six or more pair of abdominal prolegs(which lack chrochet ), one lateral ocellus on each side of head. 

Apocrita :(wasps,bees,ants)

The body has a distinct waist. 

The first segment of the abdomen is incorporated into the thorax. A narrow region called the petiole joins this to the rest of the abdomen, called the gaster.

Characterized by Larvae that feed on other Arthropods. 

The larvae are maggotlike.

Have narrow junction between thorax and abdomen. 

Contain largest no. of species. 

Node is usually present. 

Further divided into:- Terebrantia(parasitica) which use their ovipositor for egg laying and the Aculeata, which have the ovipositor modified as a sting. 

Reference

australian.museum

ento.csiro.au

Projects.ncsu.edu

tolweb.org

britannica.com