Mantis eats Minnow in Captivity and ruminations on evolution

Subject: Mantid eating a minnow
Location: Evergreen Park, IL
November 23, 2013 1:36 pm
I always bring some mantids in before a hard freeze and then put the oothecae outside to help ensure future generations(usually after mating, the first three ootheca will be fertile but none afterward). The females can get quite hungry after laying their ootheca and will gladly eat a minnow. I don’t think you’ll see that in the wild though 🙂
Signature: Ozzy

Mantid eats Minnow
Mantid eats Minnow

Hi Ozzy,
Thanks for sending us your photo of a Mantis eating a Minnow in captivity.  Your comment about the unlikeliness of seeing this in the wild struck a chord with us.  Just yesterday, while working in the yard, we thought about how man has affected the evolution of the creatures around us.  Often when we think of evolution, people get wrapped up in the origin of new species, but appearance and behavior of existing species also constitutes a type of evolution.  Since many insects, including many Mantids, only live a single season, it is possible to witness an evolutionary change during a single person’s life span.  If you continued to feed minnows to Mantids, and then included a bowl of water containing live minnows in your habitat, the Mantids might eventually learn to fish for those minnows.  Subsequent offspring might eventually carry the gene that includes the instinct to fish, and when those individuals are then released into the wild, they might eventually spawn a population of Fishing Mantids.  We realize this is a very far fetched scenario, however, we do believe that nurture affects nature.

2 thoughts on “Mantis eats Minnow in Captivity and ruminations on evolution”

  1. As cool as that would sound, it just isn’t possible to inherit an acquired trait like that. A population of fishing mantids could come about if the next generation learned it from their parents, but this girl’s genes won’t be changed by her learning.

    • Thanks for your input Joshua. We weren’t really serious, but we were playfully pondering the possibilities. What we do know is that through generations, insects and other creatures develop instinctual behaviors that are not learned, but somehow passed from generation to generation. We also know that inherited characteristics are passed from generation to generation. If learned behavior can eventually become instinctual, then it might be hereditary. As conditions change, including things like climactic conditions, only the creatures that adapt can survive. We really haven’t been studying creatures long enough to know if instinctual behavior can be modified when environmental conditions change. We admit that stating that Mantids might eventually learn to fish is a fantasy, but how did Fishing Spiders learn to fish? We will likely never know because the changes are so gradual and the written record is so brief that time erases evidence.


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