Stunning, sly, and ruthless, with legs  that go all the way to her abdomen,  

this bulbous beauty could knock  you out with just one bite.

But don't jump to conclusions.

This iconic arachnid is mostly misunderstood.

She's not a bad girl, she just looks like one.

This is the Black Widow.

Hi, I'm Danielle Dufault and  you're watching Animalogic.

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Black widows are a type of spider perhaps best  known for... well you know, sexual cannibalism.

That memorable behaviour is where  the Black Widow got its name.

But you might be surprised to learn  that the rumours of their treachery  

are greatly exaggerated.

There are over 30 species of Black Widow,  

ScarJo notwithstanding, but only a few of those  choose to make their lovers a post-coital snack.

So let's not stereotype these venomous vixens.

Some Black Widow sport the iconic all black body,  

and the red hour-glass shaped  markings on their abdomen.

But most species actually come  in a wide variety of colours,  

from brown, to red, to completely black.

Their life expectancy also  depends on their species.

Females generally live a lot longer, and  are much, much, larger than the males.

Black Widows have been around for about a hundred  million years and can be found all over the world.

They like warm, dry climates, and  prefer to spin their webs in dark,  

sheltered spots close to the ground.

They feed on flies, mosquitos, beetles,  caterpillars, worms, grasshoppers, and hydra.

You know, typical spider food.

When the Black Widow catches their prey,  

they wrap more silk around them,  and paralyze them with venom.

Their venom is 15 times more  toxic than a rattlesnakes.

Not exactly a peaceful death.

Black Widows use their sense of smell  for a lot of the same things we do:  

avoiding predators, tracking  down food, and finding shelter.

But chemoreception is far more important for them.

It's actually their main means of communication.

The chemicals used to communicate  are called pheromones.

Most people associate the word with  scents that make you attractive.

But in the animal kingdom,  they play a much larger role.

Pheromones have been used since  some of the very first animals,  

and possibly by other lifeforms before them.

When it's time to mate, the female Black Widow  releases pheromone-laced silk onto her web.

Those pheromones evaporate into  the air and float far and wide,  

acting as a siren song to attract potential mates.

"Come to my web, you cannot resist me!"

Thank you, that is my impression  of Lolth, Queen of spiders.

The pheromone signal becomes strong thanks to  a process called sender-receiver co-evolution.

The females who send the  most attractive chemicals,  

are the most likely to pass their  genes onto the next generation.

Enter the male widow.

Like the females, this little guy has inherited  quite the impressive genes from his fore-spiders:  

the ability to detect female  pheromones in an ocean of chemicals.

It's thanks to evolution that these two have  mastered the science of sexual communication.

It's time for this male to show off just how  good he is at picking up on sexy signals.

If he's actively searching for a  mate, he'll crawl up to a high place  

and wave his arms around a bunch.

And then, he'll smell them to see  if he's caught any pheromones.

Very subtle stuff.

When he gets a hit, this spider heads straight  to his potential partner, like a moth to a flame.

Or, you know, like a male  spider to a Black Widow's web.

Some of you may be thinking, "Oh  no, this poor little spider-man  

he has no clue he's about to become brunch."

But, remember, only a few  species are sexual cannibals.

And for those femme fatales  famous for feeding on males?

Well it's only if they're in the mood for a snack.

If the male is smart, he'll  mate with her after she's eaten.

How does he know if she's full?

Chemoreception!

If his sense of smell tells  him that she's starving,  

he instinctively knows not to get any closer.

The female's web is covered  in pheromonal discharge.

Now we get to see how those  pheromones work via direct contact.

When the male touches the web,  

he's sort of tasting the female's pheromones,  and gets kicked into romance mode.

The chemicals trigger his courting behaviour.

This doesn't mean wine,  roses, and back rubs. Nope!

Black Widows opt for vibrations.

The female Black Widow doesn't even  care that her mate seems weak and tiny.

She's more concerned about his moves.

And although her pheromones may have  communicated she was looking for a mate,  

she may not be entirely sold on this male.

Get off!

Then his plan hits a snag.

Another, bigger male, who's also been attracted by  the female's pheromones, wants to shoot his shot.

And he's not wasting any time!

He immediately mounts the female Black Widow!

And it's on!

The two spiders battle it out  for the female's attention.

Who will win?

Even though the smaller male put in  all the hard work to court the female,  

the new guy has the edge because of his size.

Please take it somewhere else boys!

As usual, the bigger male wins out.

Now to enjoy his success.

He tries his luck at inserting his two  palps, the sexual organs around his fangs  

that look like black balls, into the female's  epigynum... the genital opening on her abdomen.

Success!

As soon as the palp goes inside the female,  

it curls up like a spring and  then he gives her his sperm.

Aw, how sweet!

Mating can last up to 20 minutes.

Right about now, those hypnotic  pheromones start to wear off.

Will the male end up in the mouth of his mate?

Or is this his lucky day?

He walks away unscathed.

He managed to survive a tango  with the iconic Black Widow.

What a badge of honour!

Once the male leaves, the female can now  lay her eggs in a gorgeous silky egg sack.

These sacks can hold up to 300 eggs,  

and the sperm her male partner gave her  can produce up to 10 viable egg sacs.

Which means, this one tryst could  result in 3,000 new baby spiders.

Bye bye bikinis.

All in all, a highly productive  day for Black Widows.

Well done, you two!

A credit to your species!

So what should we talk about next?

Please let me know in the comments and be  sure to subscribe for new episodes every week.

Thanks for watching, see you later.