BATFLIES: Nature's hitchikers

SPECIES CLASSIFICATION

The batfly is a eukaryotic animal, meaning that its genetic information is enveloped in the nucleus [5]. Eukaryotic-wise, they can be further narrowed down into the animalia category. Animals such as batflies classified in this category have human-like qualities such as having embryos in the early ages of embryonic development, able to breathe in oxygen, sexually reproducing, and having the ability to ingest organic matter [6]. Tapering the batfly’s classification even more, this is where we start to see qualities that we can observe upon glancing. In the Anthropod category, animals do not have a backbone (invertebrates). Instead, they have an exoskeleton in distinct fragments. For them to mature, they must shed the exoskeleton to develop. These are the characteristics of animals that are classified as Arthropods [7]. The next categorization builds onto the observed attributes mentioned above, the insecta class. Animals classified in the insecta class all possess three distinct body segments: the head, the thorax, and the abdomen [8]. In the description of insects, batflies take it to the extreme. Therefore, they’re further categorized into the Nycteribiidae category [9]. This is the family for batflies; with the description of winglessness, small head and long legs. At rest, the small head can tuck into a groove in the thorax [2, 9].

EVOLUTIONARY AND ADAPTATION HISTORY

Based on the phylogenetic tree on the right, batflies belong to the superfamily Hippoboscoidea. This suggests that batflies share common characteristics with Muscoidea and Oestroidea, considering they belong in the clade of Calypterata [3]. Because of that, one can assume that the Muscoidea, Oestroidea, and Hippoboscoidea branched off from the Calypterata with aid from the requirements for natural selection to happen. There was also a selective pressure from the environment that drove the Calypterata to have different species, also driving the speciation of this clade. With nearly 300 species of batflies in the world, a continuity between them all is that they all live on bats, but the variable lies in their diet, behavior, and host specificity [10]. Some have especially adapted to feed on blood of bats, where some, like the New Zealand batfly, feed on organic material. This speciation in the consummation material shows a probable specification to come in the Nycteribiidae family (batflies) [2]. Due to the species of batflies spending a good majority of their entire lives nested on the fur of bats, some have lost their abilities to fly, shying them of wings [10]. With their environment centered around the bodies and furs of bats, some species have evolved to not rely on their vision; hence some batflies are blind and solely rely on vibration, sense light, and sense of feel to navigate navigate in addition to the constant movement of their host, it is crucial for batflies to hang on tight and not fling off. Hence, it poses a great reliance on grippy legs. Species of the batfly have evolved remarkable claws to hang on tight to the fur of their bat host. If anything goes wrong with the grip, they are pretty much done for as their whole life depends on its host. Many batfly species feed on the blood of its host, therefore it poses a much-needed dependability on strong legs [10]. In terms of batfly evolution, one can conclude that it needed constant evolvement to keep up with its environment, such as in the cases mentioned above.  

BODY STRUCTURE AND SIMILARITIES TO OTHERS

            As mentioned before, batflies belong in the insecta class which denotes their body structure. This means that they have three body regions. Specific to the batfly, they have spiderlike legs. The long legs of a batfly, like in other insects, are homologous structures. They share a common evolutionary origin and basic characteristics with legs found in other insect groups. Even though there are variations in the function and developmental pathways, the leg formation are conserved across insects. Additionally, some batflies possess wings and some are non-functional. Therefore, there are batflies with vestigial wings, further proving the unity of batflies speciation and closeness to its relatives [12].

FINAL THOUGHTS

            All in all, batflies are pretty scary-looking creatures but they are underappreciated due to their looks. Reading this blog and not knowing about its looks beforehand, one can associate this animal as cute and friendly based on the depiction of its behavior. However, if one were to show them pictures of how they look, their thoughts would be completely different. According to Piotr Naskrecki, a wildlife photographer, he’s taken a photograph of a batfly nesting on its host, where the host seemed to be in distress. Many people have seen the picture on Facebook, and reported the picture as graphic and was therefore taken down [10]. This shows the extent to which people judge animals based on their appearance alone, without considering their behavior. For some species, batflies benefit their hosts as they help to maintain the hygiene of their hosts by removing dirt and debris [10]. One connection I have to make that really connects the themes of evolution and natural selection is through studies we did in class. Take tuskless elephants for example. In this study, natural selection favors elephants with no tusks since the selective pressure was aiming for tusked elephanst. In the case of batflies and the study of tuskless elephants, both cases illustrate how natural selection acts on specific traits to shape populations in response to environmental pressures. By learning about the story of batflies, we can foster a deeper understanding and respect for nature and its beauty.