If you’re single, and you’ve ever been interested in someone whose lifestyle is very different from your own–which in the Jewish world usually means religiously–you’ve likely heard the phrase, “A bird may love a fish, but where will they build a house?” Or maybe you’re a fan of classic Broadway and know that “fish gotta swim, birds gotta fly.” Well, what if those assumptions were not true?

Now , according to the Daily Mail, nature weighs in on “religious” difference affecting living arrangements, with the mangrove killfish. This violently named fish spends several months of every year out of the water and living inside trees.

Hidden away inside rotten branches and trunks, the remarkable creatures
temporarily alter their biological makeup so they can breathe air. Biologists studying the killifish say they astonished it can cope for so long out of its natural habitat.

These changes are only temporary, altering to permit the fish to live in the tree for a while; at some point, the fish reverses its composition and returns to the water. This fish is more adaptable than most single people.

Forget the creepiness of a fish that can haul itself onto dry land and find shelter in a tree; this was an exciting discovery. If fish can live in trees, then maybe there can be compromise when it comes to religious differences? To carry through the metaphor, will there be a point at which “a fish” and “a bird” could conceivably build “a house” together? Is this nature’s pro-intermarriage polemic?

Not so fast…

Apparently, the killfish was previously best known for one other bizarre quirk: they are the only known vertebrate (animal with a backbone) to reproduce without the need for a mate.

Killifish can develop both female and male sexual organs, and fertilise
their eggs while they are still in the body, laying tiny embryos into
the water.

This is nature’s irony: that the most adaptable of species are too independent to require companionship. Is such a species to be pitied, or is there a lesson to be learned?

[crossposted to MyUrbanKvetch]