Embryonic Geniuses?
Who would’ve thought red-eyed tree frogs were any different from any other frog on the planet? It happens to be that these little embryos are pretty in tune with their surroundings, even as early as one day after being brought (layed?) into the world.
Normally the frog momma lays her eggs on leaves that dangle over tropical ponds. Tropical areas are known for their violent storms but even though the worst of the winds, the eggs stay put! It is one thing to make it though a storm, but what if a hungry predator wanted a frog egg omlette for breakfast? If a snake or something similar were to bite at the egg cluster, it would cause shaking and the older embryos would “know” to flee! No, they don’t sprout legs and move elsewhere; they “emergency hatch”! This sends a rain of new tadpoles into the water, often saving around 80% of the frogs-to-be.
Of course these little smarties don’t stop here. Scientists have found that the red-eyed tree frog embryos develop big feathery gills for extracting oxygen from the watery substance in the egg. The part of the egg that is closest to the air typically carries twice the oxygen concentration of the deep interior part of the egg queezed in closely among neighboring sibling sacs. Curious, one scientist decided to try to prod the embryos so that their gills fell into the low-oxygen zone. Most of the 3-day-old embryos twiched themselves back into place within 15 seconds! Even the 1-day-old embryos (which have no blood and no heart; only tiny hair-like projections to help movement) managed to get themselves at least halfway back to the oxygen-rich area within 5 minutes.
Not too shabby for a cluster of mush!
Photo Credit: K. Warkentin/Boston Univ. and Smithsonian Tropical Research Institute
