Its not the biggest aquarium on the planet, but the Berlin Aquarium is a fantastic destination and well worth your time and investment. The aquarium has been around since 1913 and has a phenomenal level of biodiversity that must be seen to be believed.
What follows is a sampling of the creatures present at the aquarium with a bias on imaging of the creatures eyes because… well, we like eyes.
The jellyfish or Cnidaria are some of the first creatures you’ll see when entering the aquarium.
There are a variety of smaller fresh and salt water tanks for different species of fish distributed around the aquarium that provide some amazing opportunities to see varied fish from around the planet.
Then there is an amazing tank for the Chondrichthyes that includes some spectacular examples of sharks and rays.
Of course they had Pterois or lion fish as well. These fish have been very popular aquarium fish despite their venomous spines. Their popularity has resulted in them being released into the wild in areas where they are not indigenous, causing huge problems. In fact, on the last trip to the Dry Tortugas in Florida, we were admonished to let park rangers know if we came across any and they would send out a lion fish hit squad to get them.
Perhaps my favorite fish at the aquarium was the mudskippers. These amphibious gobies use their pectoral fins to “walk” on land and have amazing eyes that provide panoramic views around their heads. Remarkably, they can retract these eyes into the head like a periscope to clear the eye surface from debris. But more importantly, the optics of these eyes allow them to see both in the water and in the air through modified lens and corneas. The retinas are apparently almost exclusively cone dominated like many fishes, but unlike most fishes the ratio of cone photoreceptors to ganglion cells is very different with many more ganglion cells than in many other fish.
Crocodiles, turtles and frogs of all kinds are upstairs at the aquarium as well as a bunch of invertebrate species that I did not get any photos of.
I was really excited however to see the really well developed parietal eye on these iguanas. Perhaps it was because Robert and I had been talking about parietal eyes in the fossil record on our walk through the Museum für Naturkunde just before. I can feel a grant proposal coming on, but one that would never be funded through NIH…