Watch 1,000 baby spiders devour their mothers and aunties alive in stomach-turning, first-of-its-kind footage

Filmmakers have captured first-of-its-kind, spine-chilling footage of young spiders cannibalizing their mothers and other elderly relatives en masse.

In the video, more than 1,000 young African social spiders (Stegodyphus dumicola) creep out of their nest in search of their next meal. The youngsters appear to play a macabre game of "statues" as they move, before suddenly freezing then moving again in unison.

The young spiders first attack and devour an insect caught in the giant web that holds their nest, tearing at its body while the insect is still alive. But when this source of food runs out, the spiders turn to one of the moms of the nest, whose condition is deteriorating fast after producing so many young.

"The demands of parenthood are finally taking their toll," British biologist and broadcaster Sir David Attenborough says in his narration of the clip, which is from a new five-part series from the BBC called "Parenthood."

Related: Starving cannibalistic spiders won't hunt their siblings, but they'll quickly dine on their corpses

But the dying spider mom has a departing gift: Trembling, she waits for her offspring and their cousins to swarm and cannibalize her. "Her's is the ultimate sacrifice, born out of a need to ensure the survival of the next generation," Attenborough says.

Scientists think African social spider moms tremble on purpose while waiting for their gruesome deaths. The vibrations they create may be similar to those made by insects that get caught in the web, so young spiders don't hesitate to attack their moms.

However, after eating the spider mom, the spiderlings still aren't satiated. They move on to their other surviving relatives, "eating every adult in the colony one by one until the next generation is all that is left," Attenborough says.

The clip is the first time TV cameras have captured this stomach-churning behavior, according to The Guardian. Attenborough was both "delighted and horrified" when he saw the footage, Jeff Wilson, the producer and director of "Parenthood," told the newspaper.

"When you step away from it and from the horror of it, it sort of makes sense," Wilson said.