In my email today, I ran across a fascinating article about a wonder of biology.
From: ScienceDaily (Feb. 24, 2010) — Just because cricket moms abandon their eggs before they hatch doesn't mean they don't pass wisdom along to their babies. New research in the American Naturalist shows that crickets can warn their unborn babies about potential predator threats.
And the answer is: Nobody knows for sure! But scientists have a guess. But before I get to that guess, here's the background story:
Some researchers at the University of South Carolina Upstate in Spartanburg and Indiana State University did an experiment with pregnant crickets.
In one enclosure, they put some pregnant crickets in with a wolf spider. And, if you think You're afraid of wolf spiders, imagine the stress of those poor mamma crickets!
Wolf spiders are venomous and can cause a very nasty, painful wound on people. Thankfully, most people only suffer pain, itching and swelling for from a few minutes to a few days.
However, the wolf spiders in the experiments were only able to stalk the crickets, not kill them. The researchers somehow covered their fangs with wax, which somehow made the spiders safe. Now, I don't know the particulars about the wax job - my sources didn't elaborate.
Anyway, in a second enclosure, some more pregnant crickets were kept without a wolf spider to harass them. This is known as the Control Group.
Okay, so now, after the crickets laid their eggs, the researchers then compared the behavior of those offspring of crickets that were terrorized by a wolf spider to those offspring whose mothers hadn't been exposed to spiders. And, Guess What?
When placed into a terrarium with a hungry wolf spider, the crickets born of spider-exposed mothers were more likely to seek shelter and stay there. They stayed hidden over 100 percent longer -- and lived to tell the story more often -- than offspring from mothers that hadn't been exposed to spiders.
From Science Daily: Another experiment showed that the "forewarned" crickets were more likely to freeze when they encountered spider silk or feces -- a behavior that could prevent them from being detected by a nearby spider.
The results suggest that "the transfer of information from mother to offspring about predation risk, in the absence of any parental care, may be more common than one might think," Storm said.
Now, all this, apparently, doesn't just apply to crickets in the lab. The researchers also found that wild baby crickets in areas with lots of spiders tended to be more cautious in the presence of spider signs like spider webs. And of course, when those crickets were collected and put through the same paces as the lab-reared crickets, they tended to stay alive longer than baby crickets that were reared in safer wild environments.
The researchers also said their findings suggest a transfer of information from mother to offspring about predation risk might be more common than thought.
Now for the guess of how this might happen that I mentioned earlier: The researchers say that it is possible that stressful events like predator attacks trigger the release of a hormone that influences the development of the embryo.
And that's pretty much all she wrote folks! As far as the facts in this article go anyway. But I'm thinking the story won't really end there - I have a feeling that scientists are curious critters, and that they won't let this go by any means. They'll keep poking and prodding and mucking about with crickets and spiders and maybe some other creatures, until they get to the bottom of it. At least I hope they do! Because I'm still curious and I want to know more.
Parting thought: Could these findings apply to humans? If hormones, or whatever, actually Can have such far-reaching effects on behavior after birth, are we prisoners to our biology? Or are we the beneficiaries of biology? Can we truly give our children advantages before they are even born? Can we avoid instilling negative behaviors in our fetuses? And, just How might we do that?
Sign me Wondering!
MLA Source Citation: University of Chicago Press Journals. "Crickets 'Forewarn' Unborn Babies About Spiders." ScienceDaily 24 February 2010. 1 March 2010