You’re at a beach-side store in line to purchase an over-priced water bottle, where you find yourself feverishly rummaging the still-wet pockets of your swim suit, hoping to amass enough coins. “That’ll be $4.34 for the 8oz water bottle,” says the perpetually annoyed man behind the counter. And, under worried breaths, you regurgitate your collected coins in front of the cashier. After counting out your pocket change, he raises his left brow and responds with completely void of empathy, “You’ve only given me $3.38. How about you come back with a sand dollar later, huh? Next!”
Are They Actually Money?
The dollar-coin looking Sand dollars were given their monetary moniker by seagoers who discovered their washed-up, dried-out skeletons littering coastal beaches. And, while there’s no chronology behind the adoption their common name, “sand dollars” have accumulated a number of different names across their endemic ranges; New Zelander’s call them sea cookies or sea biscuits, for example.
Thankfully They’re Not Prickly
Essentially, sand dollars are just pancake-flat sea urchins…without the prickly bits. And, unlike most urchins, sand dollars are fossorial in low-tide, burying themselves underneath the moist sand. However, you can clearly tell which ones didn’t successfully shade themselves from the harsh summer suns; they’re being sold at the nearby beach shop.
Inflation From Reproduction
Sand dollars are echinoderms, belonging to the same class of animals as seastars and other sea urchins. Asexualy speaking, sand dollars able to create identical clones of themselves, should a large chunk their body become detached that contains they’re central nerve network. And, vice-versa, they’re able to regenerate that now aloof segment via their intact nerve network; it’s truly a natural marvel worth a YouTube inquiry.
Now on the sexual side, both male and female gender roles do exist in the sand dollar taxa. That being said, their procreation is far from committal. Male and female sand dollars, under the optimal temporal conditions, will release their gametic bodies into the water column with the hopes of them externally fertilizing in the open sea.