Mantises are some of the most impressive insects on the planet. There’s more than 2,400 species worldwide, and if there’s one insect I’m really glad isn’t human-sized, it’s the praying mantis – these guys are terrifyingly efficient hunters.

They’re typically ambush predators, patiently waiting for unsuspecting prey to wander past. They have impressive vision and some species are able to turn their heads almost a full 180 degrees. When prey is located, the mantis lunges forward and uses the spines on its forearms to hold onto its future dinner. While mantises usually feed on other insects, they have also been known to hunt much larger prey, including lizards, frogs, fish and even hummingbirds! (I highly recommend Googling this if you don’t believe me)

Not only are they really good at murdering things, they’re also really good at avoiding being murdered. Most species have the ability to fly, and those that do have an auditory chamber in their metathorax, which is just a fancy way of saying they have a single ear in the middle of their chest! But this isn’t just any regular ear –  it can only hear ultrasound, because of course it can. How badass are mantises?

In many species, this ear has evolved in order to detect the echolocatory calls of predatory bats. If an approaching bat is identified by a flying mantis, the mantis immediately begins spiralling downwards to reach the relative safety of the ground as quickly as possible.

Once they’re on solid ground, mantises employ their other superpower – camouflage. Now most camouflagers in the animal kingdom just try to look like the thing they’re sitting on, but mantises take it a step further. They’re known to gently rock from side to side in an attempt to mimic leaves and branches swaying in the wind. It’s also theorised that this kind of movement allows for improved depth perception, helping mantises distinguish between background and foreground objects.

If you’re thinking that you may have underestimated how cool mantises are, you should probably strap yourself in for the remainder of this post. We’re just getting started…

This is a Giant Rainforest Mantis. That’s right, he’s a giant. Look into his eyes and tell him he’s not a giant. I dare you…

Okay, so maybe he’s not a giant yet. This little guy is still a nymph – a mantis on its way to becoming an adult.

The life cycle of a mantis begins in the leadup to winter (or any time in the tropics). The female creates a kind of frothy mixture from her abdomen, into which she deposits anywhere between 10 and 400 eggs, depending on the species. This froth hardens and forms a protective capsule referred to as an ootheca (such a cool name). In temperate climates, the female typically dies and the baby mantises wait until winter is over before they hatch. In tropical environments, the eggs hatch after 3-6 weeks.

Once hatched, the mantis is referred to as a nymph. Nymphs start off very small and often mimic ants to avoid being eaten. A nymph will shed its exoskeleton five to ten times before reaching its adult form, and only develops wings after its final moult. Mantises usually only live for about six months, and upon reaching adulthood, they only have one goal in mind.

We’ve discussed the life cycle of a baby mantis, but where do baby mantises come from? I’m SO glad you asked.

Mantises are the ultimate femme fatale of the animal kingdom.

I’m sure a lot of you are aware that female mantises often engage in a practice called ‘sexual cannibalism’, whereby the female eats the male after mating. In the wild, around a quarter of male-female encounters result in the male becoming dinner. However, that’s just the tip of the iceberg.

Did you also know that male mantises are able to CONTINUE MATING without their heads?! I swear I’m not making this up. While getting down to business, the female will regularly begin devouring the male, starting with his head. Undeterred, the male is like ‘oh well, I didn’t need my head to do this anyway’.

Experiments show that males do try to avoid being eaten, as this allows them to mate with multiple females. HOWEVER (and I’m going to quote directly from Wikipedia here because this phrasing was just too good) – once a male has begun to be cannibalised, “the male’s movements may become even more vigorous”, and there is “a quantifiable increase in the duration of copulation… in some cases doubling both the duration and the chance of fertilisation”.

In other words, males prefer not to be eaten, but if forced to choose between sex and survival, they decide to go out with a bang. The theory is that the brain is responsible for self-control, and once the male’s brain is eaten by the female, he just loses all inhibition. Consequently, encounters in which the males are eaten tend to be more successful at producing healthy offspring, not just because the male mates more… umm… enthusiastically, but also because the female gets a nutritious meal to help with the development of her young.

So in the mantis world, males are often, quite literally, mindless sex objects. However, the males should probably be grateful for this existence, because in one species of mantis, the males don’t exist at all…

Across the southern United States, there exists a unique mantis known as Brunner’s Stick Mantis. Why so unique? They’re the only species of mantis to have done away with males entirely. Every mantis of this species is female, and they reproduce through a process known as parthenogenesis (literally Greek for ‘virgin creation’).

I never studied biology, and when you Google parthenogenesis, a lot of the explanations include fancy words like meiosis and automixis. I still don’t quite get it, and I’m not 100% convinced it’s not just an elaborate sci-fi plot, but in a nutshell, here’s how it works.

An egg cell is developed through a process called meiosis, and this egg contains half the mother’s genetic material. However, the process of meiosis also produces a number of smaller cells as a by-product. The egg then merges with one of these smaller cells to create viable offspring. This process slightly alters the genetic material to ensure that the offspring are similar to their mother, but are not perfect clones. This type of parthenogenesis is called automixis.

There’s another type of parthenogenesis called apomixis, however this typically occurs in plants and results in genetically identical clones of the parent.

Parthenogenesis has been observed in a wide variety of species, from California Condors to Komodo Dragons, often surprising zookeepers when live young are produced in the complete absence of a male. It’s thought that parthenogenesis might be an inbuilt, last-ditch survival mechanism for animals that find themselves trapped without the ability to reproduce. However, for Brunner’s Stick Mantises, they decided to make parthenogenesis the norm rather than the exception.

From mating without their head, to reproducing without mating at all, mantises tend to listen to the basic rules of biology through their ultrasonic chest ear, and then laugh in biology’s face. These incredible creatures are some of the most unique insects on the planet, and I hope you’ve enjoyed learning about them!

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Photos:
Red-Eyed Mantis (Hierodula sp.), Berry Springs, NT
Curvy-Butt Mantis (Archimantis sp.), Caranbirini Conservation Reserve, Australia
Giant Rainforest Mantis Nymph (Hierodula majuscula), Daintree Rainforest, Australia
Female Rainforest Mantis devouring a male Rainforest Mantis (Hierodula majuscula), Daintree Rainforest, Australia
Tree Runner Mantis (Ciulfina sp.), Darwin Botanical Gardens, Australia