Welcome back to the latest edition of the Barrier Island Naturalist blog! As many of you may have experienced while visiting us, there are always new things to learn about nature and our earthly environment. Even as naturalists (or especially as naturalists), there are plenty of new questions that we don’t know the answer to. Sound a little nerve-wracking? Actually, it’s the opposite! We all love learning new information so much that we have created a game of it. “Stump the Naturalist” is the latest trend sweeping the island, a daring game of scientific exploration combined with the real-time excitement of being out in nature. Here are some questions (and then answers) from this week’s Stump the Naturalist sessions. Before scrolling to discover the answers, see what hypotheses you can come up with first!
Stump the Naturalist:
- “How fast do ghost crabs dig?”
- “How do ghost shrimp poop outside of their holes?”
- “What is the deadliest snake in the world?”
- “How many teeth will a shark have in its lifetime?”
- “How much venom does it take for a rattlesnake to kill you?”
- “Do fish sleep?”
- “Would a salt water fish survive in fresh water, or vice versa? Why?”
- “Why do bubbles come out of ghost shrimp holes?”
- “Why aren’t there any squid or jellyfish in the aquarium?”
- “Why can’t a cannonball jellyfish sting me?”
- “How fast do ghost crabs dig?” – While we haven’t found any data yet that examines how fast ghost crabs can dig, we do know that they can move on land at speeds up to 10 mph! This places the ghost crab at the top of the list for quickly moving crustaceans.
- “How do ghost shrimp poop outside their holes?” – We have yet to discover any definitive research on this subject, but we certainly have a few hypotheses! Our best guess is that as the ghost shrimp expel excess water from their holes, the chocolate sprinkle-like fecal pellets are carried with it.
- “What is the deadliest snake in the world?” – There are a few different ways to answer this question. If we consider “deadliest” to mean the snake that causes the most human deaths each year, we would have to give the title to the saw-scaled viper. There are currently eight different identified species of saw-scaled vipers, all of which are relatively small (measuring no more than 3 ft. at their largest). While their venom is not as potent as that of other snakes, their aggressive nature, quickness to strike, and proximity to humans is what makes them so lethal. They live in dry areas above the equator across Africa, Asia, India, and the Middle East.
Now, if we answer this question by naming the most venomous snake in the world, the inland tapian takes the cake. There are three recognized species of taipan, all indigenous to Australia. Since the taipan feeds primarily on small mammals, its venom is specifically adapted to target mammalian bodies (like ours). Its venom contains a hair-raising combination of neurotoxins that 1) binds nerves to muscles, rendering neural pathways that enable movement completely useless; 2) eats away at muscle and tissue, flushing the dead matter through kidneys and often causing kidney failure; and 3) thins the blood so much that either the victim bleeds out, or hemorrhaging occurs.
For more information about snake venom, visit this toxinology database.
- “How many teeth will a shark have in its lifetime?” – Sharks have several rows of teeth in their mouth at one time so that any lost teeth can quickly be replaced. Depending on the species, sharks can go through anywhere from 30,000-50,000 teeth in a lifetime!
- “How much venom does it take for a rattlesnake to kill you?” – While most rattlesnake bites do not prove to be lethal (given the availability of fast medical treatment and antivenin, sometimes called antivenom, availability in the Southern US), they certainly can be if bites go untreated. rattlesnake venom contains hemotoxins that destroy red blood cells and eat away at tissue. According to research completed by Dr. William K. Hayes at Loma Linda Medical University (the location where Venom ER was filmed!), rattlesnakes will actually meter their venom, meaning they have some control over how much venom goes into each bite. His research shows that Southern Pacific rattle snakes will deliver about 60mg of venom on the first bite to a decoy human hand, then about 57 mg on the second bite, and finally about 30 mg on the third consecutive bite.
- “Do fish sleep?” – All animals need some form of rest, and while that may look different from the way we humans sleep, it performs a similar function. Different fish find rest in different ways. Some fish will burrow in the sand or wedge themselves into coral to conserve energy in safety. Other fish can float in place thanks to a “swim bladder,” or air-filled organ that allows fish to remain stationary in the water.
- “Would a salt water fish survive in fresh water, or vice versa? Why?” – While some species of fish, called euryhaline fish, can indeed live in both fresh and saltwater environments, most fish can only live in one or the other. Fish cells undergo a process called osmosis, where water passes in and between cells. In osmosis, higher concentrations of salt will move to areas of lower concentrations of salt in order to achieve balance. As such, the salt in saltwater effectively draws water out of cells. Saltwater fish have special adaptations that allow them to regulate osmosis and salt intake in different ways; some fish have special enzymes on their gills that filter salt, while others can pass enormous amounts of salt each day through urination (just like humans). Freshwater fish do not have these adaptations, and would quickly dehydrate and die in a saltwater environment. Because of osmosis and the high content of salt already in saltwater fish, saltwater fish in a freshwater environment would essentially flood their cells with freshwater and cause the cells to burst.
- “Why do bubbles come out of ghost shrimp holes?” – As we addressed previously, we think that ghost shrimp are consistently expelling excess water that leaks into their holes.
- “Why aren’t there any squid or jellyfish in the aquarium?”– Believe it or not, squid and jellyfish cannot survive in square tanks (which is what we have), only round ones! Since they primarily move forward, they can work themselves into a corner and become stuck there. Round tanks will allow them to gently bump their way around the tank without this obstacle.
- “Why can’t a cannonball jellyfish sting me?” – During their time here at BI, most students will see some cannonball jellyfish washed up along shore, aptly named for their large dome-like shape. Thankfully, these jellyfish do not have a harmful sting even though they still possess the stinging cells called nematocysts. When threatened, the cannonball jellyfish will secrete a toxic mucus that is harmful to some fish and small crustaceans, but may only mildly irritate human skin, eyes, mouths, or noses. Feel free to check them out when you see them on the beach, but make sure it is a cannonball before you touch it!
We hope you learned as much as we did this week!
See you soon,