Butterflies' Fascination: Why Do They Like Turtles?

Butterflies and turtles have a symbiotic relationship where butterflies drink turtle tears as a source of sodium and other nutrients, and in turn, the turtles get their eyes cleaned. This behaviour is called lachryphagy, which means to feed on tears. Butterflies need sodium for their metabolism and egg production, and while turtles get sodium through their carnivorous diet, butterflies cannot obtain it from meat.

Butterflies drink turtle tears as a source of sodium

Butterflies and turtles have an interesting symbiotic relationship. Butterflies drink turtle tears as a source of sodium, which is otherwise missing from their diet of nectar, water, and fruit. Sodium is essential for a butterfly's metabolism and egg production. While butterflies get their required sodium, turtles get their eyes cleaned by the butterflies.

This behaviour is called lachryphagy, and the relationship between butterflies and turtles is called commensalism, where one species benefits, and the other remains unaffected. In this case, butterflies are the ones benefiting from the relationship.

The sight of butterflies drinking tears from turtles is fascinating and beautiful. Tropical entomologist and science communicator Phil Torres described the sight as "one of the most bizarre, strange, beautiful, fascinating things I have ever seen in my entire life."

The behaviour of butterflies drinking turtle tears is not limited to turtles. Butterflies have also been known to drink sweat and urine to obtain sodium.

Butterflies also get sodium from dirt, dung, sweat, and urine

Butterflies require sodium for reproduction. While they get most of their nutrition from flower nectar, this does not provide them with enough sodium. Therefore, they must seek out other sources of sodium to supplement their diet. Butterflies can get sodium from dirt, dung, sweat, and urine.

Dirt

Mineral-rich mud is a common source of sodium for butterflies. On sunny days after rainfall, butterflies can be observed gathering around mud puddles to sip moisture and take in the salts and minerals from the soil. This behaviour is called "puddling" and is mostly performed by male butterflies, as they incorporate the extra nutrients into their sperm.

Dung

Butterflies can also obtain sodium from animal dung, with a preference for the dung of carnivores, which tends to have a higher sodium content than that of herbivores.

Sweat and Urine

In addition to dirt and dung, butterflies can procure sodium from animal sweat and urine. This may involve landing briefly on an animal's face to absorb the moisture they need.

Butterflies don't discriminate whose tears they drink

In the Amazon, where salt is scarce, butterflies have been observed flocking to the heads of yellow-spotted river turtles to drink their tears. The turtles produce tears to remove excess sodium from their bodies, and the butterflies benefit from this bystander effect. While the butterflies gain much-needed sodium, it's less clear how the turtles benefit from the arrangement. Some sources suggest that the relationship is commensalistic, where the butterflies benefit and the turtles are neither positively nor negatively affected. However, others argue that it could be parasitic if the butterflies transmit ocular diseases to the turtles or cause discomfort with their spiny proboscises.

The butterflies' behaviour is not limited to turtles, as they have also been known to drink the tears of other animals, including reptiles and humans. They don't seem to discriminate when it comes to finding their sodium fix! This fascinating evolutionary adaptation highlights the interconnectedness of different organisms and the importance of protecting all species within an ecosystem.

Butterflies may also be seeking amino acids in turtle tears

Butterflies are known to drink turtle tears, a behaviour known as lachryphagy, which means "to feed on tears". This phenomenon has been observed in the Amazon rainforest, where butterflies land on the heads of turtles and sip their tears.

The butterflies are attracted to the tears because they are a source of sodium, which is scarce in the western Amazon region. Sodium is an essential mineral for butterflies, as it is necessary for their metabolism, egg production, and flight. While turtles obtain sodium through their carnivorous diet, butterflies rely on other sources such as urine, sweat, dung, and tears.

In addition to sodium, it has been suggested that butterflies may also be seeking amino acids in turtle tears. Amino acids are the building blocks of proteins and are essential for many biological processes. Butterflies also engage in a behaviour known as mud-puddling, where they visit mud, blood, or faeces to obtain salts and amino acids.

The relationship between butterflies and turtles in this context is considered commensalism, where one species (in this case, the butterfly) benefits, while the other (the turtle) is relatively unaffected. However, it is important to note that the presence of butterflies on a turtle's head may obstruct its vision and make it more vulnerable to predators.

The relationship between butterflies and turtles is called commensalism

Butterflies and turtles have a symbiotic relationship. Butterflies drink turtle tears as a source of sodium and minerals. In turn, the turtles get their eyes cleaned. Butterflies need sodium for their metabolism and egg production, but they can't get it from flowers. So, in the Amazon, they target the tears of turtles basking in the sun.

While some people have suggested that the turtles benefit from having their eyes cleaned by the butterflies, others believe this is unlikely. The butterflies' behaviour is an example of how odd behaviours can evolve in the face of a limiting resource. In the Amazon, salt is a much-sought-after commodity as it is generally lacking in the environment.

Butterflies in this area will go to great lengths to obtain salt, including drinking from sweaty skin or backpacks. They have also been known to drink urine, sweat, and dung to obtain sodium.

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