'Mom of the year?' Mother spider feeds self to babies

The insect world may have found its ‘Mom of the Year’ in the female Stegodyphus lineatus, a desert spider that feeds herself to her young shortly after they’re hatched. This practice­, which is known as matriphagy, has been recorded in spiders before, according to Mor Salomon of the Israel Cohen Institute for Biological Control in Yehud-Monosson, Israel.

“Matriphagy was first discovered by the German arachnologist Ernst Kullmann in [the] seventies, so the behaviors of regurgitation and matriphagy are not the new discovery here,” Salomon told FoxNews.com.  “The big discovery [here] is the mechanism behind these behaviors.”

Found in the semi-arid regions of Israel and other parts of the Mediterranean basin as well as throughout the Near East and Asia Minor, the female Stegodyphus spins her webs in shrubbery. Webs studied in Salomon’s research were found in bushes near dried-up river beds in Israel’s Negev Desert.  Inside the web, she creates a silk disc that contains 70 to 80 eggs, while her intestine tissues begin to dissolve. When the “spiderlings” hatch, she pierces the silk disc, allowing the babies to emerge.

Note, dear readers, those of you with weak stomachs may want to stop reading at this point.

“[At this time] a liquid has already accumulated in her gut, allowing her to start regurgitating to her young,” Salomon said. “While she regurgitates, the process in her intestine intensifies and the liquid formed probably travels back through her intestinal tube to her mouth where she secretes it for her young.”

The babies crawl all over her head, trying to get at the liquid that is leaking from her face. She makes no attempt to escape as her young eventually pierce her soft abdomen with their mouths before feasting on the liquefied guts inside. This process takes a few hours, at the end of which their mom (otherwise known as “dinner”) is officially dead.

In the end, the mother has given all but 4 percent of her body mass to her young, who leave her heart alone. Thanks, kids!

While it might seem like a case of taking a mother’s love too far, in the spider world this is business as usual.

Stegodyphus is not the only spider genus showing matriphagy,” Salomon added. “All species in the family Eresidae (to which Stegodyphus belong) show matriphagy and there are other spider families in which it is also [involved].”

And though many may find the concept of baby spiders eating their mother’s liquefied innards revolting, Salomon suggested that it’s just another amazing example of nature at work.

“I know it looks ‘disgusting’ for someone who is not familiar, but it shows the amazing way evolution and natural selection work,” she said. “It is amazing to think that this behavior has evolved as the best way (evolutionarily) for a female to reach a high reproductive success by ‘giving herself to her young’. It really shows how the natural world is remarkable.”

The report by Salomon and her colleagues can be found in the April Journal of Arachnology.