Durophagy (eating hard-shelled prey, such as beetles or mollusks) appears as a dietary specialization among lizards, but it is rare among snakes. Why? What specializations of the teeth would you expect to find in durophagous lizards and in snakes?
What will be an ideal response?
Durophagous lizards, such as the caiman lizard (Dracena guianensis), crush crabs and snails with broad molarlike teeth in the rear of the jaws. The highly kinetic skulls of snakes cannot apply crushing force to a hard object in the mouth, and durophagous snakes have hinged teeth that fold back when they are swallowing heavily scaled lizards, such as skinks. (F. C. Patchell and R. Shine. 1986 . Hinged teeth for hard-bodied prey: A case of convergent evolution between snakes and legless lizards. Journal of Zoology 208:269–275)
You might also like to view...
Why do signs and symptoms of decreased thyroxine concentration not appear until about a week after a thyroidectomy (surgical removal of the thyroid gland)?
A) About a week's worth of thyroxine is stored in the liver. B) About a week's worth of thyroxine is stored in the anterior pituitary gland. C) Most of the thyroxine is bound to proteins in the bloodstream and the hormones are released gradually. D) The parathyroid glands can take over function of the thyroid gland for a short period of time. E) The anterior pituitary gland can start producing thyroxine.
An athlete who is nearing the end of a 2-kilometer run would be expected to have both an increased mean arterial blood pressure and an increased total peripheral resistance
Indicate whether the statement is true or false.
________ transport is required to move a substance across a membrane against a concentration gradient.
Fill in the blank(s) with the appropriate word(s).
Which of these muscles functions only to compress the abdomen?
A) external abdominal oblique muscles B) internal abdominal oblique muscles C) diaphragm D) rectus abdominis muscle E) transversus abdominis muscles