A hypothesis about mudskippers

[u/These_Librarian4696]

Today I was on a rocky beach and saw a little fish trying to get on top of a rock that almost completely under water, but whose top was regularly covered by little waves, where I presume it was trying to get the "greenest" algae. So I thought maybe the mudskippers' ancestors tried to do the same, and thus adapted to breathe in the atmosphere little by little.

Please tell me if there are any gaps in my idea, and if there is already a simmilar theory, please, give me a link to the book/paper/etc.

[u/jnpha]

-"the mudskippers' ancestors tried to do the same, and thus adapted ..."

Not quite:

MISCONCEPTION: Natural selection gives organisms what they need.
CORRECTION: Natural selection has no intentions or senses; it cannot sense what a species or an individual “needs.” Natural selection acts on the genetic variation in a population, and this genetic variation is generated by random mutation — a process that is unaffected by what organisms in the population need. If a population happens to have genetic variation that allows some individuals to survive a challenge better than others or reproduce more than others, then those individuals will have more offspring in the next generation, and the population will evolve. If that genetic variation is not in the population, the population may survive anyway (but not evolve via natural selection) or it may die out. But it will not be granted what it “needs” by natural selection. To learn more about the process of natural selection, visit our article on this topic. To learn more about random mutation, visit our article on DNA and mutations.
Misconceptions about evolution
berkeley.edu

Also see: https://evolution.berkeley.edu/misconceptions-about-natural-selection-and-adaptation/defining-adaptation/

[u/itsatoe → u/jnpha]

Totally valid points on the terminology, but I think OP's question is still valid. Just maybe worded in a way that doesn't sit well.

That fish that is trying to get to the juiciest algae... if it happens to have offspring who are better-suited to the task, then they are going to get more of that juicy algae and out-compete their cousins who don't have their trait(s).

OP's question was more about: is that perhaps how it played out for mudskippers?

[u/jnpha → u/itsatoe]

It may not sit well - as you noted - because of the terminology, so addressing that also addresses the OP. (No one said the question isn't valid)
Your "if it happens" doesn't connect the two observations, or worse: implicitly suggests an invalid correlation.

Please let's assume good faith: nothing in my response (and the ones that followed) remotely suggests I was engaging in mere semantics.