Many species of flatworms live in marine environments. They are simultaneous hermaphrodites, meaning they are both male and female. It's advantageous to be a hermaphrodite since the odds of successful reproduction are doubled. What’s the strategy for reproducing if you’re both male and female? It’s complicated. When a pair of flatworms of the same species meets, each can deliver sperm or receive it for fertilizing eggs internally. There’s a natural conflict since it takes a lot of energy to grow and carry fertilized eggs, so each animal wants to be the male.
Keep Your Friends Close, BUT! … Your Anemones CLOSER!
Sure, there were lots of reasons for Nemo to bust out of that Dentist office aquarium. In our version of the story, it was mostly because he couldn’t bear to live outside of his anemone.
Nemo is a clownfish, also known as anemonefish because these fish make their homes in anemones. Of over 1,000 anemone species worldwide, only 10 coexists with tropical clownfish. The fish and its anemone are in a symbiotic relationship – this means that the fish benefits from the anemone and vice versa.
Clownfish are the only fish capable of living in an anemone without getting stung by its tentacles. Like their relatives, jellies and corals, anemones have stinging cells on their tentacles. How do the clownfish escape being stung? They have a slimy mucus covering that protects them from the stinging tentacles. Scientists know this because they took clownfish, wiped off the covering, and found that the fish would get stung when they were returned to their home anemone.
Humpback whale: Megaptera novaeangliae photo credit: Steve Lefkovits, Pacific-Landscapes.
Humpbacks live in all the major oceans from the equator to sub-polar latitudes.
They are baleen whales: their baleen acts as a sieve straining out water as it traps small fish or plankton. Humpbacks have pleated throat grooves that open and expand, allowing a whale to gulp down huge amounts of food and water. Often the whales feed in groups, herding schools of fish and creating bubble nets that trap the fish, and then opening their huge mouths to engulf their prey.
(Metacarcinus magister, formerly Cancer magister)
Learn more about how many people along the West Coast were extremely bummed out about not having their beloved Dungness Crab at season opening in 2015-2016.
All the Better to Hug You With - Sunflower star: Pycnopodia helianthoides
This big boy is one of the largest sea stars in the world. It can grow up to one meter (39 inches) across and weigh as much as a large family cat. The sunflower star gets its name from its many arms: it can have up to 24. More arms mean more tube feet – up to 15,000. Despite its girth, the sunflower star can move as quickly as one meter (40 inches) in a minute. Abalone don’t stand a chance! Its skeleton is softer and more flexible than other sea stars. It’s a badass predator that feeds on small and large marine creatures.
Unfortunately, the sunflower star has not escaped Sea Star Wasting Syndrome plaguing stars along the west coast.
The disease begins with white lesions and dying tissue and leads to a "melting" of the sea star. Scientists have found evidence...
Giant barrel sponge Xestospongia muta
Giant barrel sponges are common inhabitants of coral reefs, especially in the Caribbean. Not only are they the largest sponges on the reef, but they also are very long lived – up tp thousands of years. Like most sponges, they pump water through their bodies to obtain food: plankton, bacteria and nutrients from the seawater.
The strawberry squid, Histeoteuthis heteropsis, aka “the green-eyed squid” is a member of a group called “the cock-eyed” squids, so named because one eye is larger than the other. Scientists think that the smaller eye has evolved to look down, watching for predators from the depths. The bigger eye looks up, trying to detect the shadows of potential prey against the very faint light from above.
But, many animals in this midwater zone make their own light so they disappear in the faint light from above – called counterillumination. In the “survival game” of evolution, the strawberry squid’s much larger eye has evolved a lens with a fluorescent pigment that absorbs blue light. Researchers at the Monterey Bay Aquarium Institute think...
Imagine huge, long-necked sauropods roaming primeval forests. The dinosaur represented above, Argentinosaurus, lived around 95 million years ago in what is today Patagonia. These giants are thought to be the largest dinosaurs ever to walk the earth, weighing up to 75 tons and growing to 130 feet long; the narrowest part of a leg might be about four feet around.
We typically think of flatworms as being pretty easy going. Not this one. The New Guinea flatworm, is a powerful predator that feeds on other worms, snails and a variety of soil-dwelling creatures. Flatworms come in many varieties, sizes and lifestyles. There are over 20,000 identified species both free-living and parasitic.
The New Guinea flatworm, a land planarian, is in the news since it made “The 100 Worst Invasive Species” list by International Union for Conservation of Nature (IUCN). It is spreading to many corners of the world, gobbling up prey as it goes. Now, the two-inch long flatworm has made it to the continental United States. So what’s the problem with having this invasive flatworm on our shores? It likely has no natural predators, which means it could wreak havoc on soil ecosystems rippling up the food chain to animals, like birds, that feed on earthworms and snails.
From IFL Science! New Guinea Flatworm, one of the Worst Known Invasive Species, Found in US
From Science Daily Discovery in the US of the New Guinea flatworm, one of the worst known invasive species
Video: Highly Invasive Snail-Eating Flatworm Species Spotted In U.S.
Is that watermelon we smell?
Nope. It’s the Melibe leonine who lives in kelp forests and eel grass beds along the Pacific coast.
Look at a melibe and you might think: jellyfish. But it’s the melibe’s head, or oral hood, that’s fooling you. To feed, a melibe extends its hood and sweeps it back and forth to catch small plankton, which it then passes to its mouth. While melibe prefer to remain attached to a surface, they can dislodge when threatened and swim by contracting their bodies.