Romance, dance dates, fancy gifts, and chastity belts…
Murderous femme fatales, jealous dudes, extortion, and mind-control…
Game of Thrones may be back on the air, but there’s another world filled with even more
violence, treachery, and plot-twists than your average Lannister party…
The sex lives of insects and spiders.
It’s kind of a free-for-all.
[INTRO]
[1.
Praying Mantis ]
Perhaps no other insect is more associated with their bad mating behavior than the female
praying mantis, who’s known for her tendency to decapitate and then devour male suitors.
And okay, yeah, the rumors are based in truth.
Kind of.
A lot of mantis ladies do this.
But mantis sexual cannibalism is actually less common than you might think -- it happens
in about 25 percent of matings in the wild.
And it isn't typically required for successful fertilization.
That said, eating your mate comes with a couple of nice perks.
For one, it’s a free meal.
Female mantises are bigger than their partners, and if they’re really hungry, a uh, preoccupied
male is an easy target.
Generally, a starving or malnourished female is much more likely to chow down on her date
than a well-fed one.
Beheading their partner in mid-copulation may also offer females an advantage that’s
a little more macabre.
You’d think severing a brain mid-hump would end the mating, but it turns out that disconnecting
the male’s brain and his body actually sparks more spasms -- and more sperm.
And though I’m sure any male would prefer to keep his life and wander off to mate another
day, those who do wind up as dinner may keep females better fed, increasing their chances
of passing along their genes.
[2.
Honey Bee]
Scientists still aren’t sure whether some male mantises deliberately offer themselves
up as a snack, but they’re not the only insects who engage in sexual suicide…
In the caste system of a honey bee hive, every bee knows its role, and male drones aren’t
much more than sperm donors.
They don’t gather pollen, or help maintain larvae or the hive’s architecture.
They don’t fight off intruders.
Really, their only job is to find queens from other hives, mate with them in mid-flight,
and go out in a blaze of glory.
See, when a successful drone uncouples from his queen, his penis and some abdominal tissues
are ripped out of him, and, well, he dies.
His passion literally rips his guts out.
Take that, poets!
Ms. Queen Bee, on the other hand, can potentially mate with dozens of drones over several mating
flights, tucking their sperm away for future use over the next few years of egg-laying
within the safety of her hive.
But don’t think unsuccessful drones have it any better -- because come autumn, those
freeloaders get kicked out of the hive by their sisters, and are left to freeze to death.
Then there are the more -- can we call them romantic?
-- bugs.
The ones who sing and dance and put on shows, or woo their loves with special gifts.
[3.
Fireflies]
When it comes to impressive visual displays, it’s hard to compete with a firefly’s
flashy light show.
These flying beetles have special light organs in their abdomens that contain a compound
called luciferin, which reacts with incoming oxygen to create that classic firefly glow.
The animals regulate this inflow of oxygen to create blinking patterns, and each species
uses its own individual flash code to attract mates, almost like a visual morse code.
A hopeful male flies around in the dark, blinking his little heart out, and if his lightshow
is good enough to catch a choosy female’s eye, she’ll start signalling back at him.
A flashy display is important, but a hopeful male also has to bring gifts if he hopes to
retain his lady friend’s interest.
Researchers from Tufts University recently found that female Photinus fireflies ultimately
selected their mates based on the size of their so-called nuptial gifts, not their light
display.
And by “gift,” I mean “packet of sperm.”
During copulation, a male passes along a pile of sperm wrapped up in a nutritious, coil-shaped
protein packet called a spermatophore that increases female fertility by providing her
developing oocytes with extra energy.
The larger the gift, the more likely she’ll accept her suitor and make him a father.
Researchers haven’t yet figured out how the female can tell which males can offer
them a bigger packet.
But to a female firefly, size does matter.
[4.
Dung Beetle]
Other animals woo with simpler gifts, and nothing wins the fair heart of a lady dung
beetle like a nice round ball of poo.
Poop is everything to a dung beetle.
They collect it, eat it, and even raise their children in it.
There’s a reason why we call them dung beetles.
After bumping into each other at, say, a fresh elephant or cow patty, some dung beetles form
a pair bond, rolling their own giant dung ball off into the sunset together.
Once they find a nice soft piece of land, they’ll bury their precious poo-ball, and
start mating, sometimes in tunnels through the dung itself.
The female lays her eggs in smaller brood balls, which will be a nice snack for her
grubs once they hatch.
In many species, one or both parents stick around and continue to care for their offspring
as they mature -- a rare behavior in the insect world.
Real salt-of-the-Earth, those dung beetles.
But not everyone is impressed with poop.
Some ladies prefer more conventional displays, like sweet dance moves.
[5.
Peacock Spider]
At just a few millimeters long, furry Australian peacock spiders are tiny.
But they’ve still got style -- I’m talking the wardrobe of Elton John and the dance skills
of Channing Tatum.
To attract female attention, a male starts out by vibrating his abdomen and waving one
pair of legs around like he’s directing traffic.
Once he’s got an audience, he pulls out the big guns, extending his colorful, iridescent
abdominal flaps and excitedly flipping them up behind his head like a peacock’s tail.
Then he shimmies around, giddily shaking his legs in the air, bouncing from side to side,
drumming the ground and shaking what his mama gave him.
It’s all very adorable.
If the object of his affection is suitably impressed, she’ll allow him to mate with
her.
If she isn’t… he’d better pack up and get out of dodge quick, or he’ll end up
as her dinner.
[6.
Mayfly]
For some insect species, like the mayfly, there is no life at all after mating.
After spending a couple of years in freshwater in their aquatic nymph stage, mayflies finally
complete their lifecycle when they hatch into delicate winged adults.
Often entire local populations hatch at the same time, in a winged frenzy of sometimes
millions of insects.
One Mississippi River population hatches in hordes of around 18 trillion animals!
This synchronicity lowers the chance of any one mayfly getting eaten, while the general
orgy environment increases their chances of getting laid... which is literally their sole
mission in life.
Seriously, they can’t even eat.
They don’t have functional mouthparts or a working digestive system.
And once they hatch, the party doesn’t last long.
Most species don’t live as adults for more than 24 hours, and one species only lasts
five minutes -- a record in the insect world.
No wonder the mayfly is classified under the order Ephemeroptera [eff-em-er-OP-ti-ruh],
from the word ephemeral, or fleeting.
Mayflies mate in mid-air, above the water, and the female then lays her eggs on the water’s
surface before collapsing.
The dying females provide a smorgasbord for local fish, the males go off to die on land,
and their fertilized eggs sink to the bottom of the water where they’ll eventually hatch
into nymphs, destined to spend only a single, glorious day in the air.
While short-lived insects like mayflies need to mate fast, other species like to take their
sweet time.
[7.
Soapberry Bug ]
Meet the long and colorful soapberry bug.
In certain climates, female soapberry bugs face higher mortality rates than males, which
leads to a skewed sex ratio and a whole lot of dudes competing for relatively few females.
Not only that, but like many insect species, females often mate with a number of males,
and it’s usually the sperm of the last male in the lineup that actually fertilizes her
eggs.
This means that male soapberry bugs have to fight to /find/ females -- and then fight
again to be the last guy on her dance card.
One way they do this is by prolonging copulation, even after insemination is long over.
Males can hang on for hours, days, or even more than a week, withdrawing only long enough
for the female to lay eggs.
This type of mating guarding can get so intense that some males will keep clutching their
mates even after the females have died.
Luckily, matings tend to be a lot quicker when populations are more balanced since competition
isn’t as high.
[8.
Fruit fly ]
On the other hand, if you’re a male Drosophila melanogaster [meh-luh-no-GAS-ter] fruitfly,
it may pay to be the first in line, not the last.
Why?
Because their seminal fluid contains special mind-controlling proteins that affect the
female’s behavior.
Some of these proteins spark cause egg production, while others seem to have an almost hypnotic
effect, making her less interested in sex with other males.
Presumably both of those things give her mate a reproductive edge over his competitors.
One study out of University of Washington suggests that the more seminal fluid a female
takes in, the greater the influence her mate has on her reproductive behavior.
That seems maybe a little messed up, but when it comes to skeezy mating tactics, one bug
really takes the lowdown prize.
[9.
Waterstrider]
Perhaps you’ve see a long-legged waterstrider, gliding over the surface of a pond with all
the grace of an Olympic skater.
Don’t be fooled -- when it comes to mating, the tactics these guys use are harsh.
When a male is in the mood to mate, he just jumps on the nearest female without bothering
to court her first.
If she’s not into it, she can actually block her vagina with a hard genital shield -- sort
of like a chastity belt -- and hope he moves on.
If he doesn’t move on, though, she might be in trouble.
He’ll start using his legs to tap out a specific rhythm on the water, attracting underwater
predators like fish and backswimmer bugs.
Because those predators attack from below, a pinned female waterstrider knows she’s
the one most likely to get snatched and eaten.
So she’ll lower her shield and give in to stop her mate from tapping.
Stay classy, waterstriders.
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