Mammals have developed astonishing dietary habits over the past 100 million years. A recent study highlights extreme adaptations for feeding exclusively on ants and termites.
This research, published in
Evolution, reveals that mammals independently evolved toward this specialized diet at least 12 times since the beginning of the Cenozoic era. These are independent evolutions, occurring in multiple unrelated species at different periods.
Illustration image Pixabay
Scientists attribute this evolutionary convergence to the massive expansion of ant and termite colonies, particularly after the extinction of dinosaurs.
Researchers compiled dietary data for 4,099 mammal species, revealing the diversity of diets in the mammalian world.
The study shows that myrmecophagous mammals share an insatiable appetite, requiring the consumption of thousands of insects each day to survive. This dietary specialization appears to be a one-way path, with little diversification once adopted.
Ants and termites now represent a significant portion of global biomass. Their abundance has influenced the evolution of many species, pushing some to adopt a diet based on these insects. This strategy, although risky, could offer advantages in the face of climate change.
A phylogenetic tree of mammals with colors representing the diet of living species and their ancestors; silhouettes of myrmecophagous mammals surround the tree. An inset diagram at top right illustrates transitions between dietary states.
Credit: Vida, Calamari, & Barden / NJIT What is myrmecophagy?
Myrmecophagy refers to the specific diet consisting of feeding primarily or exclusively on ants and termites. This feeding behavior is observed in several species of mammals, birds, and even reptiles.
Myrmecophagous species have developed morphological and physiological adaptations to capture and digest these insects. Among these adaptations are long sticky tongues, specialized claws for digging, and digestive systems capable of processing chitin, a major component of insect exoskeletons.
This diet is particularly energy-intensive, as ants and termites are nutrient-poor. Myrmecophagous animals must therefore consume enormous quantities each day to meet their energy needs.
Myrmecophagy is an example of convergent evolution, where unrelated species develop similar traits in response to common selective pressures.