London Zoo celebrated Pride Month by honoring its LGBT+ residents with a banner reading "Some penguins are gay. Get over it", a reference to the charity Stonewall's slogan "Some people are gay. Get over it".

The zoo is home to three same-sex penguin couples, Nadja and Zimmer, Dev and Martin, and (most famously) Ronnie and Reggie, both of whom are much cuter than their human namesakes. Ronnie and Reggie have been going strong since 2014, becoming foster fathers in 2015 after they adopted an abandoned egg. 

Many people might see the banner as an unoffensive reminder that homosexual behavior (different from homosexuality) exists across the animal kingdom – but not Caroline Farrow, a Catholic commentator and journalist.

Farrow takes issue with the banner, accusing the zoo of "pushing [their] values on [her] children". (Something she apparently has no issues with when the tables are turned, as her comments on other people's transgender children go to show.) She then compares the banner to "a sign saying some emus are Catholic; get over it". This makes very little sense as not a single emu is Catholic, while some penguins are indeed gay (or better: they form same-sex pairings).  

After receiving some flack for her original thread, Farrow displayed the pugnacity of the man who confused the vulva for the vagina and dug deeper, accusing the banner of "virtual signaling" and calling it "confrontational propaganda" that forces parents "to broach sensitive topics with their kids".

"Spare me the virtue signalling about gay penguins. Animals do not exhibit human sexuality. End of," Farrow tweeted.

While we – as a species – are prone to anthropomorphizing animals (see: this image of a "grieving" kangaroo), sometimes to a problematic extent, homosexual behavior has been observed in more than 1,500 species worldwide. Arguably, by suggesting that practicing homosexual behavior is exhibiting "human sexuality", it is Farrow who is politicizing the romantic behavior of the penguins and applying old-fashioned notions of human sexuality to animals.

Same-sex penguin couples have received a lot of headlines recently (see: Sphen and Magic, Jumbs and Kermit) but more than 130 species of bird have been seen engaging in homosexual behavior – lest we forget Thomas, the bisexual polyamorous goose.

Male birds of paradise are known for their distinctive plumage and extravagant mating dances, both of which evolved to seduce females and boost mating success, but older male Victoria's riflebirds are also known to woo (and on occasion, mount) younger males. Meanwhile, in one colony of Laysan albatrosses, as many as 31 percent of breeding pairs are both females. The two birds take it in turns to mate with a male bird. Then, they rear the chick together.

Closer to home, bonobos – one of the few species of animal to mate for pleasure – have been spotted engaging in homosexual behavior. Female bonobos often have sex with other females, likely as a means of bonding and social climbing. Meanwhile, homosexual behavior in females is the norm for Japanese macaques and up to 8 percent of male sheep prefer the company of other male sheep to that of fertile females.

Still, it is important not to conflate homosexual behavior (an action) with homosexuality (a human construct).

Same-sex sexual and social behavior is relatively common across the animal kingdom, including in birds, Alex Bond, senior curator in charge of birds at the Natural History Museum, told IFLScience in an email. Whereas, in general, “homosexuality” is a human construct that means someone is romantically or sexually attracted to someone of the same sex or gender.

"So it’s not really a good term to use for animals scientifically, even if it is used colloquially," he added.

"The London Zoo took a well-known campaign (from Stonewall UK) and used it to communicate about the diversity of behavior and social structures in a unique and brilliant way."