why-animals-do-the-thing:

equagga:

fishmostly:

quillicous:

quillicous:

if regular fish with swim bladder issues flip upside down, do upside down cats with swim bladder issues flip right side up

all right you fuckers i looked it up

the primary aquarium upside-down cat is Synodontis nigriventis. S. nigriventis exhibits something called a Ventral Substrate Response (VSR), meaning without other cues to orient themselves, they put their vent side closest to the substrate. They are also apparently able to “turn off” their vestibular reflexes (balance instincts) to assume a variety of postures without their body going “whoa, we upside down.” (Meyer 1976). (This means upside-down cats can’t get motion sickness. Weirdly enough.)

They also exhibit a Ventral Light Response, where they put their vent side towards illuminated surfaces (like the surface of the water, for instance, or an illuminated wall under lab conditions); this response can be overridden by the VSR (Anken & Hilbig 2009). Also, while many species of Synodontis do not swim upside down, food location can be used to convince normally-oriented species to swim upside down and upside-down species to swim right-side up. (Willoughby 1976).

Basically, the “upside-downness” does not seem to be something inherent to the buoyancy control of species of Synodontis (more to do with their vestibular reflexes). While swim bladder disorder does not seem to be at all common in Synodontis (can’t find a single report of it; I suspect it’s as common as it is in goldfish and other aquarium fishes mainly because of poor breeding), it would probably most affect the fish’s ability to perform the ventral substrate response, which may or may not make it upside down or right side up, since for them orientation doesn’t seem to have anything to do with the swim bladder.

EDIT: Swim bladder disorder isn’t a disease unto itself anyways, it’s a symptom of a number of other things, so if you induced any of those things in a Synodontis it might not even exhibit swim bladder disorder. It might be impossible for them to get swim bladder disorder. 

Also, according to Anken and Hilbig, if you put a box with an upside-down cat in it in freefall, the cat loses all sense of up and down and reverts to swimming ventral-side to the walls. I’m not sure what the purpose of this experiment was except maybe they just wanted to drop some catfish. 

References:

Anken, & Hilbig. (2009). Swimming behaviour of the upside-down swimming catfish ( Synodontis nigriventris) at high-quality microgravity – A drop-tower experiment. Advances in Space Research, 44(2), 217-220.

Meyer, D., Platt, L., & Distel, C. (1976). Postural control mechanisms in the upside-down catfish ( Synodontis nigriventris ). Journal of Comparative Physiology,110(3), 323-331.

Willoughby, N. (1976). The buoyancy and orientation of the upside‐down catfishes of the genus Synodontis (Pisces: Siluroidei. Journal of Zoology, 180(3), 291-314.

Somebody needs to put these fish in space

synodontis: more xtreme than expected

It took me so long to realize this was about catfish, not actual cats.