There exists a snail, in hydrothermic vents in the Indian Ocean, that incorporates iron particles into its shell for extra protection.
From collision detection:
Scientists discovered Crysomallon squamiferum in 1999, but they didn’t know a whole lot about the properties of its shell until this month, when a team led by MIT scientists
decided to study it carefully. The team did a pile of spectroscopic and
microscopic measurements of the shell, poked at it with a nanoindentor,
and built a computer model of its properties to simulate how well it
would hold up under various predator attacks.
The upshot, as they write in their paper (PDF here), is that the shell is “unlike any other known natural or synthetic engineered armor.”
Part of its ability to resist damage seems to be the way the shell
deforms when it’s struck: It produces cracks that dissipate the force
of the blow, and nanoparticles that injure whatever is attacking .
Also, the post uses the phrase “Darwinian evolution crossed with Burning Man”. Win.
In the Chronicle:
Foerde and her colleagues argue that when the subjects were
distracted, they learned the weather rules through a half-conscious
system of "habit memory," and that when they were undistracted, they
encoded the weather rules through what is known as the
declarative-memory system. (Indeed, brain imaging suggested that
different areas of the subjects' brains were activated during the two
That distinction is an important one for educators, Foerde says,
because information that is encoded in declarative memory is more
flexible—that is, people are more likely to be able to draw analogies
and extrapolate from it.
"If you just look at performance on the main task, you might not see
these differences," Foerde says. "But when you're teaching, you would
like to see more than simple retention of the information that you're
providing people. You'd like to see some evidence that they can use
their information in new ways."
This is one of the sanest reviews I've seen of what we know about multitasking, attention, and learning. No flailing about how the Internet is destroying civilization, but some real concerns about the compatibility of multitasking and specific tasks.