Why being 'natural' is no argument against conservatism

As illustrated e.g. here: https://www.nationalgeographic.com/science/article/homosexual-animals-debate , the notion of abundant sexual diversity within the animal kingdom is not new at all.

Much has been made from the - no doubt interesting - collage of intimate social behaviour covering a wide range of species.

As such, this biological fact - in tandem with a supposed genetic rootcause of sexual development - has been turned into a message of legitimacy for the LGBTQ community.

Allthough I recognise that legitimacy itself and support the sexual- and relational freedom of every individual, I think the gist of the argument here contains a most dangerous tendency: 

Naturalistic fallacy* - the idea we can construe what's morally right from what is naturally here.. 

The argument** referees what are actually political - often socio-economical - questions about hierarchy and human behaviour, through the scope*** of a - descriptive, not prescriptive - biological science; an encyclopedia that's simply not built to succesfully support endeavours of democratic struggle.

Meanwhile, the same argument opens up all kinds of dark alleyways lit only by the dim instruction that if we can find specific behaviours 'conserved' in the 'natural' world, they can't be bad at all: 

Once we accept that 'natural' must mean 'good' in a behavioural sense, one could argue the latter applicable to things like warfare, sexual coersion, infanticide, violence against children...

Repressive hierarchies****..

And the list goes on and on.

But why should we even consider any genetic correlates of behaviour, or the sexual preferences of chickens, ducks, dogs, monkeys or even apes, as somehow relevant to our most intimate, personal freedom? 

* A traditionally predominantly conservative frame and as such one of e.g. (****) Jordan Peterson's favourite tools, which he usually crafts by hammering down on a bunch of pseudobiopsychology with a handfull of halfwit biology.

** Usually seriously confusing biological descriptions of evolutionary cause with some kind of model for human desires and societal goals.

*** And for this cause a pretty nonsensical one, because biology simply recognises occurence of behavioural novelty as natural.