Videos of dolphins communicating both in captivity and the wild:
Amazon River Dolphin
Though commonly referred to as "Killer Whales", Orcas are actually part of the order Cetacea, which excludes whales and porpoises.
Feeding using "Bubble Net Fishing"
Here is an amazing video displaying this hunting technique used by pods of whales:
Live both in pods and solitary
More so than dolphins, many whale species prefer traveling alone or with flexible and dynamic groups. The strongest bonds occur only between a mother and her calf.
Communicate with song-like noises
Here is a prime example of two whales communicating to each other:
At around 100ft and 200 tons, Blue Whales are the largest animals to have ever existed, even larger than any species of dinosaurs.
Seals and Sea Lions
Feed on fish, crabs, birds, krill, and other available food
Live in large groups called "colonies"
Colonies can grow to thousands of seals during mating and birthing season
Southern Elephant Seals are the largest of all the Pinnipeds, growing upwards of 20ft and weighing up to 8800lbs
Gills for breathing oxygen through
On average fish have 3-7 pairs of gills
Scales often cover the body
Though this is not always true, such in the case of catfish, lampreys, hagfish, and more
Tail, Dorsal, and Pectoral fins
Live in large groups called schools
Some species prefer solitary life, such as Sailfish or Barracuda
Technically a GoPro ad, the video offers a great view of the inside a school of wild Silver Fish!
Feed on other fish, plants, and
smaller plankton and krill
Communicate mainly with
body language, though
some use sound
Composed of 3 Segments:
Head, Thorax, and Abdomen
Exoskeleton protects the
Every so often, the crustacean needs to molt, or shed it's large exoskeleton
Antennae, legs, and other
extensions specific to
body language and
Lobsters, for example, secrete special urine from their faces to communicate with each other
Often live in groups, but
some are solitary
Eat a variety of food, from small krill
and fish in the water to large fish
and other crustacean
Sharks and Rays
Sharks and Rays are special because they are both cartilagenous fish. This means that instead of bones, they are made of cartilage!
Threshers hunt by using their long tails to stun fish, and then eat them while they recover from the blow.
Angel sharks are a great example at the similarities that sharks and rays share beyond their cartilage!
Solitary versus social behaviors vary
Though mislabeled as "man-eaters", sharks appetites vary as widely as humans depending on the species.
Tiger sharks are known as the "Trash cans of the sea", while Whale Sharks tend to only eat krill and other small fish, similar to whales