Visitors to the Aquarium can often spot educators throughout the building toting a biofact — like a shark jaw, shark skin or a whale vertebra. Our educators are always poised to answer questions, and they might even teach you something new about our aquatic world.


Let's take a moment to talk about one of these special teaching tools: The whale vertebral disk. It probably came from a large baleen whale, up to 55 feet long. The giant bone was brought up by fishermen trawling for scallops on Stellwagen Bank in the late 1960s (before the Marine Mammal Protection Act of 1972). It is very similar to the disks between the vertebrae of a human spine, although whale bones are more porous and, of course, considerably larger! When the whale was alive, the holes were filled with oil, which helps with buoyancy. Being more buoyant helps the whale reach the surface to breathe.

 

After hearing the history of this bone, many people ask about trawling. Bottom trawling involves dragging large, heavy nets along the sea floor. Large metal plates and rubber wheels attached to these nets move along the bottom and can capture or crush nearly everything in their path. The nets can also level the structure of the bottom, destroying important habitats for benthic (or bottom-dwelling) organisms. This had been compared to clear-cutting a forest. This whale disk was part of that benthic structure and may have provided shelter for other animals. When it was pulled up in the fishermen’s net, it was covered with algae, barnacles and other small animals.

Currently, fishermen are experimenting with new methods of trawling that should help to prevent benthic degradation and avoid bycatch. In fact, the Aquarium is working with fishermen, engineers and marine biologists to research and develop fishing techniques that reduce bycatch of endangered non-target marine species. Learn more about these efforts on our Conservation and Research pages.

Juvenile right whale skeleton at the Aquarium

The next time you're at the Aquarium, keep an eye out for an educator with this important biofact. Try looking up, too. Check out the right whale skeleton hanging from the ceiling. Can you find the vertebrae? How many are there? How many do you think people have?

You never know what you're going to learn during a trip to the Aquarium, or a troll around our blogs.

When you visit The Trust Family Foundation Shark and Ray Touch Tank, you probably will have only a few seconds to touch a shark before it swims past you. But find one of our educators in the exhibit, and you could have a chance to spend a lot more time with some shark skin.




One of the biofacts that educators bring into the touch tank exhibit is a piece of sand tiger shark skin (shown at left). When you get up close to the skin, you can see that it has tiny scales called dermal denticles (“tiny skin teeth”). Dermal denticles point tailward, so when you feel shark skin from head to tail, it feels smooth, but from tail to head, it feels coarse like sandpaper. The denticles are also strong, giving the shark a flexible, armor-like skin. This helps reduce drag and allows the shark to move more quickly through the water.



If you take a closer look at the skin, you may find something else amazing. Look for small holes or pores—those are the Ampullae of Lorenzini. Located around the snout and under the mouth of a shark, these special organs can sense the electrical fields in the water, giving sharks their “sixth sense”! They help the shark find food and may assist in locating birthing grounds.

White spotted bamboo shark

You can learn a lot about the animals in The Trust Family Foundation Shark and Ray Touch Tank from the educators working in the exhibit. And they usually bring some interesting visual aids along with them, too.

You might see one of them holding what looks like an elongated, dried out dumpling with strings trailing from it. What could it be?

Well, some sharks give birth to live young, but other sharks lay egg cases with embryos inside. The biofact (A biofact is a combination of the words artifact and biology, used to refer to preserved items such as animal bones, skins, molts and eggs.) below on the right is actually an egg case laid by a white spotted bamboo shark.

White spotted bamboo shark egg cases

White spotted bamboo sharks are a type of bottom-dwelling shark found in the Pacific Ocean from Madagascar to Indonesia and Japan. They are a type of oviparous shark, which means they lay eggs that hatch outside of the body. Once the male fertilizes the eggs, the female has the hard task of finding a safe spot to lay them.

In many sharks that lay eggs, the embryo takes several months to grow and hatch. By finding a secure hiding spot, the female can increase the embryo's chance of survival. In many places, females will find a spot around coral reefs or among the roots of mangroves. She attaches the eggs by wrapping a sticky tendril around the reef or root to help anchor the case.

Baby shark development inside casing.

The white spotted bamboo shark, as well as many other shark and fish species, rely on mangroves (learn more about mangroves on the Global Explorers Blog) as nurseries and places to rest. Without them, these animals would have a hard time raising their young.

Whitespotted bamboo sharks are listed as Near Threatened. They are hunted in India, Thailand, and China for human consumption and for traditional Asian medicines and they are also threatened by the destruction of mangrove habitat that occurs when coastal areas are developed.

When you visit The Trust Family Foundation Shark and Ray Touch Tank, you're guaranteed to see some live cownose rays and Atlantic rays swimming around the mangrove habitat. But you might also be lucky enough to run into one of our educators carrying a biofact of a shark or a ray. A biofact is an artifact from an animal, like a jaw or a tooth, like this one.



This is a cownose ray jaw. The teeth of the ray are close together and flat, creating a surface for cracking open shells—like a nutcracker.




The ray finds food buried in the sand and uses its fins and gills to move the sediment out of the way, creating a depression. Once the food is uncovered, the prey is seized and drawn into the mouth. Shells are crunched into small pieces and the ray gets lunch!









The cownose ray is found throughout a large part of the Western Atlantic, from the Chesapeake Bay to Florida and the Gulf of Mexico. The rays live along inshore waters with sandy or muddy bottoms. These types of habitats are perfect for finding food including lobsters, clams, oysters and fish. And to help eat these hard-shelled items, the ray has the perfect crushing jaw.

-Jo