23 September 2022

There's a reason these frogs are called Hyla VERSICOLOR


For the past several weeks we've had frogs on our windows picking off mosquitoes and moths that come to the windows at night.  Coincidentally, this week I found a blog post at Naturespeak [dead] about the Gray Tree Frog, and learned that they can change colors:
"It takes around a half hour for an individual to change color. They do so by controlling the pigment in their star-shaped skin cells. Though they can only go from green to gray and back again, they can also control the intensity of the dark splotch pattern found on the back. The sides appear to stay gray for the most part regardless of the chosen back color. Against natural settings, Gray Tree Frogs are masters of camouflage. Since the color choice is primarily intended for the daytime rest period (they are nocturnal) Gray Tree Frogs can pass the daylight hours in either color mode depending on background.  In the photo below, this fellow was resting up against the chunk of bark and his pattern matched perfectly. The second photo is of the same frog at night, at which time he was in green mode..."
Photo credit Gerry Wykes.

Reposted from 2010 to accompany a new post.

5 comments:

  1. I am afraid this may be a victim of link rot. Which is a shame, I was interested in seeing the other picture mentioned, will see if I can track down an alternative version.

    While I am writing, I'll take the opportunity to say thank you for many years of very interesting, thoughtful and informative posts, appreciated.

    Josh

    ReplyDelete
    Replies
    1. You're correct; I should have tested the link before reposting.

      Delete
  2. As a follow-up, this amazing frog appears to be one of five (or at minimum five) North American frogs that are freeze tolerant. It appears to be the only one that primarily uses glycerol to protect against freezing.

    "Five species of frogs from North America survive extensive freezing of their body fluids to temperatures as low as –8°C for periods lasting at least 2 wk"
    Source: https://onlinelibrary.wiley.com/doi/abs/10.1002/jez.1030

    "H. versicolor can mobilize its major cryoprotectant, glycerol, in response to extended cold acclimation, which is unique in comparison to other freeze-tolerant frogs, and it experiences only moderate organ dehydration during freezing."
    Source: https://onlinelibrary.wiley.com/doi/abs/10.1002/jez.1030

    ReplyDelete
  3. Chernobyl black frogs reveal evolution in action

    https://phys.org/news/2022-09-chernobyl-black-frogs-reveal-evolution.html

    ReplyDelete