Three men on deck of the H.M.S. Challenger studying Medusae jellyfish

HMS Challenger and the History of Science at Sea

Sailing ships were once used as scientific instruments themselves, but in the 1800s, ships like the Challenger were transformed into floating laboratories.
Edgar Allan Poe with some seashell illustrations from The Conchologist’s First Book

Edgar Allan Poe (Sort of) Wrote a Book About Seashells

The American writer was an enthusiast of the sciences, which may explain his decision to “adapt” a text about seashells for publication under his own name.
Fish swimming in underwater kelp forest

Turf Algae and Kelp Forests

Structurally complex kelp forests, pushed beyond their tipping points, are being replaced by mat-like, low-structure turf algae around the world.
Limnoria quadripunctata, male and female, ventral view.

How “Termites of the Sea” Have Shaped Maritime Technology

These small marine pests have been eating our ships for millennia, forcing us to keep building better boats throughout history.
Elysia clarki

Solar-Powered Sea Slugs and Survival in Future Seas

These Florida mollusks make off with chloroplasts from algae and cleverly photosynthesize them for their own nutrition.
Black-Tip Reef Sharks in shallow water lagoon, Fakarava, Tahiti

Sharks Are Hiding from Scientists in Plain Sight—Almost

Marine biologists need to count sharks to save them, but the common practice of using video cameras to record populations could be improved.
Copepod

The Little Plankton That Could

Arguably the world's most abundant animal, calanoid copepods can leap like whoa Nelly. And check out their enigmatic embryos!
Atlantic horseshoe crab (Polyphemus occidentalis) illustration from Zoology of New york (1842 - 1844) by James Ellsworth De Kay (1792-1851).

The Horseshoe Crab: Same as It Ever Was?

The seemingly static appearance of these ancient-looking arthropods presents a challenge for scientists who want to study their evolutionary history.
Many cassiopea xamachana, upside down jellyfish

Upside-Down Jellyfish and the Mucus of Death

You could get stung by a jellyfish even when there don't seem to be any around. Meet Cassiopea xamachana and its "stinging water" weirdness.
An octopus

Stuck in the Midden with You

A midden is, among other things, a refuse site outside an octopus' home. (Release the Køkkenmødding!)