"The example of those who take associates other than God is like that of the spider who takes (i.e.  constructs) a home.  And indeed, the weakest of homes is the home of the spider, if they only knew." (Quran 29:41)

This verse of the Quran comes from chapter 29, the Spider.  The part of interest here is that God mentions that the weakest of all homes is that of a spider.  In the rich Arabic language, the word "Awhan" is translated into the (weakest); and a deeper look into the meaning suggests that it means severe weakness and helplessness both physically and mentally.   

With the expansion of the study of nature and wildlife in the 20^th and 21^st centuries naturalists and scientists have unraveled, documented and videoed truly bizarre observations in the life of spiders.

Sexual Cannibalism

Out of the over 45,000 known species of spiders, it is very common that male spiders are killed and eaten by their female spouses[1]; a term known as sexual cannibalism.   It is not known why this occurs, however, one theory suggested by scientists is that the male's body provides the female with much-needed nutrients that enables her to lay healthy eggs.  A study by Spain's Experimental Station of Arid Zone revealed that in most spider species, aggressive females kill their mates indiscriminately regardless if the male is considered inferior or not.[2]  In many species, female spiders even kill potential mates they are not interested to mate with.[3]

Cannibal Jumping Spider - Credit: Shawn M.  Wilder

In some spider species, such as the dark fishing spider, the male spider automatically dies after mating due to internal reasons; and is then cruelly eaten by his bride.[4]  Other male spider species die automatically after mating only a few times and in the vast majority of species females outlive males; with males living for only a few months and females a few years.   

When lucky enough to mate and survive the ordeal, the smaller sized male spiders, knowing their spouse's cannibalistic instinct, will then immediately make a run for their lives[5]  leaving the female to nurse anywhere from a few dozen to around a thousand eggs all by herself.  Such is the case with the Brazilian Wandering Spider. 

In a further twist to spiders' lethal mating customs a study released by researchers Lenka Sentenska and Stano Pekar, from Masaryk University in the Czech Republic in 2013, found that in the Micaria Sociabilis species of black widow spiders both female and male spiders commonly kill and eat the other after mating; and that in this specific species, contrary to what was believed, male spiders more commonly kill and eat their spouses than females kill males.[6]

Life as a Spiderling

In the vast majority of species, the newly born spiderlings have only their mother to feed and protect them.  When food becomes scarce the mother is forced to feed her young unhatched eggs; hence a young spiderling must go through the trauma of eating their own unborn brothers and sisters to stay alive.[7]

When there are no more unhatched eggs to feed on and not enough insects falling into the web or caught by mother another common observation is that spiderlings, in desperation, turn cannibal on each other and the small overcrowded web turns into a confined cage of massacre.  Helpless as is she is, the mother spider also commonly engages in killing and eating her own young just to get through another day.    

[1] Pappas, Stephanie.  June 2016.  Male Orb-Web Spiders Are Choosy About Their Cannibal Mate.  Live Science.  Retrieved from http://www.livescience.com/54944-male-orb-web-spiders-choosy-about-cannibal-mate.html

[2] Gannon, Megan.  April 2014.  Food vs.  Sex: Why Some Female Spiders Eat Males Before Mating.  Live Science.  Retrieved from http://www.livescience.com/45066-virgin-female-spiders-eat-males.html

[3] Gannon, Megan.  April 2014.  Food vs.  Sex: Why Some Female Spiders Eat Males Before Mating.  Live Science.  Retrieved from http://www.livescience.com/45066-virgin-female-spiders-eat-males.html

[4] Lewis, Tanya.  June 2013.  Tough Love: Male Spiders Die for Sex.  Live Science.  Retrieved from http://www.livescience.com/37536-spiders-die-for-sex.html

[5] Szalay, Jessie.  December 2014.  Tarantula Facts.  Live Science.  Retrieved from http://www.livescience.com/39963-tarantula.html

[6] Cadieux-Shaw, Lillianne.  May 2013.  Study: Male Black Widow Spiders eat their Mates too.  Canadian Geographic.  Retrieved from http://www.canadiangeographic.ca/article/study-male-black-widow-spiders-eat-their-mates-too

[7] Englehaupt, Erika.  February 2014.  Some Animals …facts.  Science News.  Retrieved from https://www.sciencenews.org/blog/gory-details/some-animals-eat-their-moms-and-other-cannibalism-facts