sensory nervous system

Short: It’s Complicated

Cas touched a knuckle to a bead of condensation that had begun crawling down the side of the bottle’s brown glass; the surface tension on the droplet burst and Cas lifted away half the droplet to examine, turning his hand this way and that. Dean watched Cas’s careful study for the space of several heartbeats before he asked, in a soft voice so as not to startle the angel, “What do you see?”

“Hmm?” Cas flicked his eyes upward at Dean.

“You were looking at it pretty hard. What did you see that was so special?”

“Oh.” Cas shrugged, grabbing the bottle and lifting it to his lips. “It’s…complicated,” he said after a long sip.

Dean swallowed a sip of his own. “Try me,” he offered.

Keep reading

Can plants talk to each other? It certainly doesn’t seem that way: They don’t have complex sensory or nervous systems, like animals do, and they look pretty passive. But odd as it sounds, plants can communicate with each other — especially when they’re under attack. 

From the TED-Ed Lesson Can plants talk to each other? - Richard Karban

Animation by Yukai Du / @yukaidu 

  • Domain: Eukarya
  • Supergroup: Lophotrochozoans
  • Phylum: Mollusca
  • Class: Cephalopoda

Cephalopods are smart; they have a complex sensory capability, well-developed nervous systems, and can learn complex tasks. They are the only molluscs with a closed circulatory system. Some cephalopods precisely mimic their environment and can change both their color pattern and apparent texture. Octopus and squid have beak-like jaws which they use to inject an immobilizing poison into their prey. When attacked, dark ink is expelled into the siphon, and the cephalopod escapes behind a “smoke screen”.

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