What is beauty? The simplest answer is that it’s a combination of qualities culturally conditioned into the eye of the beholder to draw you in and move you. 

The effect beauty provokes in the viewer or reader is a feeling of wonder, a kind of trembling awe that pulls you in and traps you. To know when a work of art or a film is beautiful, we rely on our own aesthetic sense, which is partly inherent and partly conditioned. Our sense of aesthetic helps us shape our reality, whether in abstract or in evolution. 

The idea of a definable, objective beauty and aesthetic sense is generally controversial — especially when we apply it to animals. The reason behind the controversy is that we don’t fully understand beauty as an idea, so we cannot yet investigate its evolutionary purpose. Even though biologists have sought to explain the purpose of an intrinsic aesthetic sense for decades, they agree that, to have an aesthetic sense, the onlooker needs to have an ability to assess, evaluate, and even rank choices. 

In some developments of natural selection in evolutionary theory, humans and animals evaluate ornaments subjectively and cognitively. In nature, Charles Darwin used the term ‘ornaments’ to describe physical displays to court and attract mates — characteristics seen in animals that are more decorative than critical to survival. He called this process ‘sexual selection.’ But for a long period of time, this theory was dismissed because it put too much evolutionary credit on the female animals’ selectiveness in choosing a mate. 

While Darwin didn’t think it was necessary to make a direct link between beauty and survival, aesthetic preferences in animals are an adaptation in their environment — a step closer to becoming a successful creature that can ultimately survive better. 

Some examples of animals that use ornaments are best seen in birds, insects, and fish. While ornaments in female birds are generally less extravagant and even obvious, a 2022 study published in Nature Communications found that similar to male birds, the ornamentation of female birds helps achieve reproductive success in addition to other factors such as role signalling. 

Bowerbirds are animal architects renowned for their courtship practices. Male bowerbirds construct a bower — a nest that is built exclusively to attract females — with showy, colourful objects. They can look like either a kind of tipi structure or a walk-down-the-aisle structure with a tunnel at the end, similar to human wedding ceremonies. This ritual may include plumage, man made objects like bottle caps, and flower petals. In fact, bowerbirds may take their artistic skills further and include acorns, shells, charcoal, and even butterfly wings and crushed fruit. 

To understand if these birds prefer certain colours over others, a 2006 study on ornament colour selection was carried out. The study found that bowerbirds prefer colours that are distinct from their own plumage, bower structure, and nearby visual background. The birds disliked hues that were common colours, and chose contrasting colours instead to attract females. Bowerbirds also position the bower and its surrounding objects to influence the female’s perspective — a forced illusion that would draw her attention. 

Does this make the bird an artist? Not necessarily. While the bird does exhibit artful and aesthetic judgment, one of the study’s authors says that the purpose of its art object has no direct function other than influencing the behaviour of the viewer. 

An article in the Communicative and Integrative Biology journal claims that the Darwinian approach to understanding aesthetic judgment is “the active choice among different art objects or individuals leading to change of fitness in both artist and judge.” Therefore, aesthetics is the ability to exercise judgment.