The oldest ancestor of rabbits is a 53 million year old fossil consisting of two recognizably lagomorphine (rabbits, hares, and pikas are lagomorphs) feet. These feet belonged to an animal the size of a hamster. However, I do not want to focus on two small feet this week. Instead, let us look at the opposite end of the size spectrum. We have all seen enormous rabbits, but have any of you seen the largest fossil rabbit? I got trapped in a Wikipedia loop of bunnies looking up the Minorcan King of the Hares, Nuralagus rex. Discovered and described in 2011, Nuralagus was approximately 0.5 m (1.64 ft) tall and may have weighed around 12 kg (26 lbs). For comparison, the largest breed of domesticated rabbits, the Flemish Giant, has an average weight of 6.80 kg (15 lbs).
Nuralagus fossils have been recovered exclusively from the scrubland areas of Minorca, a small island of Spain approximately 402 km (250 miles) south of Barcelona. The discovery of the rabbit fossils in the scrublands indicates that the diet of these rabbits was most likely centered on roots and tubers of the small scrub plants. Some might wonder how an animal like a rabbit, surviving on roots and tubers might become so large. Foster's Rule, also called the "Island Rule" states that large animals with scarce resources tend to evolve to smaller sizes and small animals continue to be small except in the absence of predators which allows lineages to evolve to larger sizes.
|Figure 3 from Quintana et al., 2011.|