Thoughts on lobsters? I really like them, especially Norwegian, squat, and reef lobsters (:
Lobsters are some really funky creatures, I love them.
^ Enoplometopus or Reef Lobster
1. As far as we know, lobsters don't stop growing. They don't live forever, like some people say, but they never stop growing! (Although under the right circumstances, they can live for a long time- the oldest known lobster was 140 years old!)
2. They will eat each other. This is actually a reason why lobster farms aren't really a thing- the enclosed lobsters will literally eat each other.
^ Nephrops norvegicus or Norwegian Lobster
3. Lobsters have a gastric mill, which is sort of like teeth in the stomach. This is how lobsters and many other invertebrates chew their food. The teeth-like fixtures grind it up in the stomach.
4. They do have some regenerative powers. It takes a while, usually up to a few years, but they can regrow claws.
^ Scyllaridae or Slipper Lobsters (my favorite family of lobsters)
5. Lobsters have a dominant claw, kinda like people. They can also be ambidextrous.
6. Lobster blood is colorless until it’s exposed to oxygen, then it becomes blue!
This specimen is relatively small. P. diogenes is the world’s second-largest hermit crab species, growing large enough to inhabit a full sized queen conch shell and beaten only by the terrestrial coconut crab, which is a hermit crab that stops using shells when it matures.
I can only assume that the the “diogenes” in its name comes from some parallel drawn between the hermit crab’s shell and the philosopher’s habit of sleeping in a large jar.
This 90-million-year-old crab had the eyes of a hunter
A scattering of fossilized 90-million-year-old crabs shows how an animal might turn from bottom feeder to dragonfly-like predator. Callichimaera perplexa, first identified from fossils in Colombia in 2019, lived in the warm oceans of the mid-Cretaceous. And they had truly enormous eyes: An entire adult crab was about the size of a quarter, and the eyes set in its head took up about 16 percent of that. A human with a proportionate anatomy would have dinner plate-sized peepers.
Seven of the crabs are so well preserved that in a recent paper published in the journal iScience, a team of paleontologists could examine the facets of their compound eyes, and even the shape of the nerves between eyes and brains. That tissue suggested that the C. perplexa, or chimaera crab, saw almost as sharply as a dragonfly, and more sharply than a mantis shrimp, which hunts snails and crabs.
The paper: https://www.sciencedirect.com/science/article/pii/S2589004221015492
Truly awesome news for crab lovers this week!
I remember when this baby was first discovered and it sure gained a lot of attention with its bizarre look.
As for those of you that came for the crab meme, be not disappointed:
“There’s sort of a debate over what makes a crab,” says Jenkins. The word is used to describe both an evolutionary group, like “mammals,” and unrelated organisms that share a basic shape, like “trees.” “[C. perplexa] is a true crab in the sense that it belongs to this group that evolved during a certain time. It gives us insight into what it means to be a crab.”
Luque points out that although many animals have stumbled upon the “crab” body shape, there are even more examples of crabs evolving into another shape—as C. perplexa demonstrates. It could be that crabbiness is also a platform for adapting to new ecosystems. “You don’t see lobsters climbing trees, and you don’t see shrimp living on beaches,” Luque says. “Crabs have done that all, and more.”
So while a crabby lifestyle might come with benefits, this fossil creature demonstrates that it’s not always the best option. Sometimes it’s better to be a baby crab.
The mangrove tree crab (Aratus pisonii) is a small tree-dwelling crab found on coastlines from Florida to South America wherever mangroves grow.
Not only are they acrobatic climbers that spend most of their time in mangroves, they feed mainly on mangrove leaves, and are responsible for 90% of herbivory that occurs in mangrove forests. Nevertheless, like most crabs they’re omnivorous scavengers and will descend from the trees at low tide to feed on carrion and other ocean debris.
I also observed one climbing the trunk of a big oak tree several meters from the nearest source of water.