three things tagged “marine biology”

Diatoms

They look like priceless brooches and are tremendously important to our planet.

A photo of diatoms through a microscope

Emphases mine:

Living diatoms make up a significant portion of the Earth’s biomass: they generate about 20 to 50 percent of the oxygen produced on the planet each year, take in over 6.7 billion metric tons of silicon each year from the waters in which they live, and constitute nearly half of the organic material found in the oceans. The shells of dead diatoms can reach as much as a half-mile (800 m) deep on the ocean floor, and the entire Amazon basin is fertilized annually by 27 million tons of diatom shell dust transported by transatlantic winds from the African Sahara, much of it from the Bodélé Depression, which was once made up of a system of fresh-water lakes.

Wikipedia

The Blue Ringed Octopus

Some absolutely marvelous photos of a Southen Blue-Ringed Octopus by @SammyGlennDives

Southen Blue-Ringed Octopus 1

Like she’s dancing!

Southen Blue-Ringed Octopus 2
Southen Blue-Ringed Octopus 3

Would love to find out what kind of protective gear the photographer had on. But it seems like the octopuses are very shy and will attack only when provoked, which is when their rings become more intense 🐙 The salivary venom1, synthesized by bacteria and not the octopus itself, doesn’t have an antidote and is only used to hunt and defend. It’s either injected via the beak, or is sprayed as a mist, paralysing the prey in either case for the final kill (presumably involving more beak.)

Here’s a little more. Love the intro. They truly are so alien and so, so beautiful 😍

  1. Always have to look it up: Poison is passive, venom is active. ↩︎