Why are there virtually no marine insects

This is one of the issues all aquatic insects face: getting enough oxygen in aquatic habitats with a respiratory system that evolved on land. Have you ever noticed that you float more easily in the ocean or salt lakes than in freshwater? Well, the same thing happens to air-filled insects. Better for them to stay along the shores where there are more things to hold on to at the bottom! Mangroves are nice, hospitable places for marine insects compared to the open ocean.

Crustaceans are close relatives of insects and have lived in the ocean since before insects evolved, so crustaceans may already live in the places the insects might attempt to colonize. But, the crustaceans have been there longer and can out-compete their land-evolved brethren.

A crustacean filling a niche an insect might use? If you want to learn more, I recently discovered that the book on marine insects Marine Insects , edited by the great marine entomologist Lanna Cheng is available online and as a PDF.

I encourage you to check it out! Really amazing. The open ocean, as seen on a foggy day from Point Reyes, California. Thanks for the clear explanation about this. And yes, mangroves are more hospitable for marine insects. There are many mangroves where I live and the biodiversity that can be found there is great! What kinds of things do you find there? Oh, there are crabs, birds, iguanas, a particular kind of shrimp and at night, I know of three mangrove areas here that have the most beautiful bioluminescence ever.

A wonderful Friday 5! Just re-read your posts on aquatic insect respiration. Are there really no adults that retain gills they had as a nymph?

They typically either sit near the surface to breathe or carry air bubbles with them underwater that they use like scuba tanks. No adult aquatic insects I know of have true gills and the vast majority of them either carry air under their wings or carry gas films to act as physical gills instead.

But then, most things that have gills are things that evolved in water. Why have crustaceans never developed into anything like water striders except, of course, the ones that did develop into water striders, the long way around.

Aquatic things, things that have been aquatic throughout evolutionary history, tend to have a hard time breathing and maintaining their water levels on out of water. Of course, there are lots of other reasons why crustaceans never became striders too! Perhaps something as simple as having their claws at the tip of their feet rather than further up their legs like water striders do is enough to break through the surface film?

And now I have a great image of a lobster running around on the surface of the ocean. How completely cool would that be??!! Now that you mention the breathing issue, it occurs to me that there are a fair number of crustaceans in the water strider habitat, they just do it from the other side of the surface, hanging below the layer of surface tension instead of walking on top of it.

They are everywhere. But these reports are similar to those of insects at sea. In any case, both copepods and insects are wondered if evolution. You are commenting using your WordPress. You are commenting using your Google account. You are commenting using your Twitter account. You are commenting using your Facebook account. Notify me of new comments via email. Notify me of new posts via email.

Skip to content Before I start this post, I would like to make it clear that I am not an entomologist, so I apologize if I say anything very wrong; I hope not. Insects are everywhere on land We also have evolutionary reasons for the absence of major numbers of insects at sea; It is believed that insects evolved from crustaceans more than million years ago and that their evolution was closely linked to that of plants. Like this: Like Loading Leave a Reply Cancel reply Enter your comment here The female is a bit smaller than the male which can grow to around 5 centimeters 2 inches and has menacing looking horns.

These beetles live off of fruits and sap flows from tree wounds. Also called the magnificent flower beetle, these mighty beasts can live up to five months. One of the world's greatest experts on butterflies and moths was German entomologist Adalbert Seitz.

Born in , he edited the monumental volume Macrolepidoptera of the World. Elaborately illustrated with over color plates, four of its volumes were dedicated to the moths and butterflies of Africa. Started in , the unfinished project was only stopped after Seitz's death. Not all insects are helpful and some are even downright dangerous. The tiny mosquito is at home on every continent except the Antarctic, but is especially bad for Africa. It only takes one bite from certain species of the Anopheles mosquito genus to transmit malaria and last year over million people became ill with the disease.

In Africa, a child dies of malaria every two minutes. One African insect that is not trying to blend in is Madagascar's vibrantly technicolored rainbow milkweed locust. As the name suggests, besides being colorful, this grasshoppers' diet consists primarily of milkweed, which makes it a highly toxic dinner for predators. Officially named Phymateus saxosus, these locusts can grow to about 10 centimeters 4 inches.

A subspecies of the Western honeybee, these social insects live in central and southern Africa. Slightly smaller than their European cousin they also produce less honey. But don't let their fuzzy upper body fool you — their sting is more potent than the Western honeybee. Yet despite their link to the "killer bees" spreading around the world these hard workers still have an important job to do.

Many people see insects as annoying pests. But British biologist Dave Goulson cautions: A world without insects is a dull place without coffee and chocolate — and with dead animals and cow patties piling up. Two separate studies highlight a dramatic trend in Germany: the number of flying insects has declined by 76 percent over the past 27 years.

There are 15 percent fewer birds than just twelve years ago. Intensive modern agriculture still relies on wild birds, bees and beasts for pollination. But these species — and whole industrial supply chains that depend on them — are at risk, according to a new global survey.

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