[ad_1]
Hey—are you an oxygen-depleted countercurrent gas exchange? Cause you take my breath away 🦀💨
Crabs have an internal set of gills to breathe, just like fish—although they work a little differently. Fish have an opening behind the gills, so water can be drawn in through the mouth, flow over the gills and exit through an external gill flap. Crabs draw water in through small openings near their legs, where it flows over their gills and out through openings by their mouth.
But shoretainly you’ve sea-n a crab, like this little striped shore crab friend, wandering around on dry land? Crab gills can still function out of water so long as they are damp (similar to how amphibians’ skin must remain moist to breathe even though they have lungs). Oxygen from the atmosphere diffuses into the water on their gills, and then into their open-circulatory blood system thanks to a fancy process called countercurrent exchange. Scientists think that by blowing bubbles while out-of-water, crabs increase their breathable surface area until they can find some water to scuttle back into. Adorable AND functional fashion!
[ad_2]
Source link
