Gray Tree Frog - Part 1

In an interlude from talking about slugs, I'd like to show you some photos I took of a little gray tree frog (Hyla chrysoscelis) that hopped into our backyard this afternoon. You can find more information about the species at http://srelherp.uga.edu/anurans/hylchr.htm.

Here you can clearly see the circular ear a little ways back from the eye. In contrast to our ears, a frog's tympanic membranes (eardrums) are exposed.

In this photo you can see one of the distinctive markings: the black hour-glass shape on its back.

Notice the separation of the three toes and the stripes on its leg.

Here you can see the white patch under its eye, a feature that can be used to identify the species.

Here is a diagram of a frog's eye:

http://www.animalcorner.co.uk/animalgroups/graphics/frogeye.jpg

Other information about a frog's anatomy (visual, tactile, motivational, and auditory) can be found at http://www.neurocomputing.org/Default.aspx.

Also, gender can be distinguished by the color of the frog's throat, a male's being dark and a female's being light. This frog's throat is white, so I assume it's a female.

While I was photographing her, I noticed that her throat was expanding and contracting rapidly. Apparently frogs can breathe without opening their mouth, through their nostrils; that movement in this frog indicated continuous respiration, perhaps because she was afraid of me, though I can't verify this. A simplified explanation of frog respiration can be found at http://www.brown.edu/Departments/Engineering/Courses/En123/MuscleExp/Frog%20Respiration.htm.