If you have ever wondered why these cute fluffballs consume food in huge quantities but do not reach the size of a hippopotamus, science is ready to offer an explanation. According to a group of scientists, it is competition with larger herbivores that limits the growth of rabbits.
When looking at the diverse groups of animals, one can notice a wide range of sizes and shapes. For example, domestic dogs vary from tiny poodles to enormous Saint Bernards. Even sloths can reach impressive sizes.
However, the order Lagomorpha, which includes rabbits, does not exhibit significant growth in the wild. This is puzzling, considering that rabbits are close relatives of rodents, whose sizes range from tiny mice weighing 4 grams to capybaras weighing 50 kilograms. So why do rabbits remain so small?
To investigate this question, a team from Kyoto conducted a study on the evolution of lagomorphs, analyzing fossils in North America and correlating them with other ecological factors. The scientists established a link between size and competition with ungulate herbivores. When lagomorphs exceed a weight of 6 kilograms, they begin to lose energy efficiency compared to ungulates, which gives the latter a competitive advantage.
Thus, the smallest ungulates in this region determine how large the largest lagomorphs can become, which has implications not only for rabbits.
