The new paper suggests that Sicilian Palaeoloxodon falconeri is in fact, the smallest advanced elephant ever discovered. All the animals from the cave, including the endemic rodent fauna, date back to 600,000 years ago, long before any humans arrived in Europe. In terms of body form and physiology, this species is perhaps the most novel, with dwarfing having brought on changes unseen in other species. The new research paper points out that these elephants have features similar to a baby mainlander. This is a condition known as “pedomorphy”, and is where juvenile features are retained in a full-grown animal.
This also gives them a very large brain in comparison to other elephants, especially when compared to mainland Palaeoloxodon. Studies of the brain mass also point out that the dwarfs probably had good cognitive abilities. This was a surprise, considering that intelligence itself is a relative concept yet the Sicilian dwarfs seem to have been ahead of the pack. Not only are the skulls somewhat rounder and shorter but even the bodies of the Sicilian elephants were markedly different from their ancestral stock. Larramendi’s skeletal reconstructions show us that the bodies of the Sicilian dwarfs were oddly dachshund-like, with long torsos and stubby legs in comparison to their mainland cousins. To see these animals standing up straight, one needs to go to the Italian capital. In 1968 Ambrosetti, one of the researchers working on the elephants, reconstructed six good skeletons based on the best specimens from the cave. Four of these were mounted later in Rome, consisting of a big adult male, an adult female, a young male and a nearly newborn male.
Larramendi’s rigorous skeletal restorations show a male, female and a baby, all compared with an adult human at full height. The male is the biggest at around a meter tall, while the baby is only as high as a pigeon or similar bird. In terms of weight, the male is still quite hefty due to his heavily built physique and short legs, tipping the scales at around 300 kilograms. This of course, is still paltry even among fellow dwarf elephants. The female, on the other hand, is 80 centimeters in height and lacks tusks. This is rather similar to modern Asian elephants, in which males in many populations have sizeable tusks and are larger than females.
The dwarfism of the Sicilian elephants may also have implications on their temperature regulation. Larramendi asserts in the new paper that land mammals over 1500 kilograms often lack body hair in hot or warm climates, although this too is a very loose rule. The researchers write in the paper that the dwarf elephants might have had a thin layer of hair covering their bodies, somewhat greater than the sparse hair on today’s elephants. The ears might have been smaller in proportion than those of a modern elephant too. Today, pachyderms use their ears to lose heat while the tiny Sicilian elephants were doing their best to conserve and retain it. What exactly would drive such massive animals to shrink down so much? The answer lies with the “island rule”.
During the warmer episodes of the Middle Pleistocene, a myriad of big and beautiful creatures lived in Southern and Eastern Europe. It was not just massive elephants making a living here. There were also wild horses and deer to rhinos, hippos and steppe bison. It was a time of mild summers and the European megafauna had plenty of grazing to do. A few of these big mainland animals did make it across the young Mediterranean though, and once they did, some discovered a new and harsh world of bare rocks, hills and scrublands. For many of the biggest animals there was no choice but to downsize, sometimes so remarkably that by the end of the process they would be virtually unrecognizable. We sometimes call islands evolutionary laboratories since many unique animals and plants may live there. Often these creatures are isolated from mainland populations, thus allowing them to have their own independence in terms of form, habits, diet or otherwise. The condition was the same thousands of years ago, and it shows quite starkly from the Mediterranean fossils.
We have not just pygmy elephants but also pint-sized hippos, deer and wild dogs spread out across the Greek islands. This phenomenon of shrinking is known as insular dwarfism. Simply put, it is the “island rule” at work. According to this general rule, huge animals grow smaller on smaller landmasses due to a lack of sufficient space or nutrition. A small body is easier to fuel than a big one. Conversely, smaller animals may become very large in response to being isolated and far from advanced predators and competition. The dwarfism or gigantism does not happen evenly though, and several factors come into play when an animal changes this much.
Availability of food and water, terrain, temperature regulation and space all need to be considered when an animal takes either direction. Thus we see normal-sized rats and mice living comfortably alongside diminutive elephants or hippopotamses on Sicily. Yet we also have a species of giant swan here that went extinct due to climate change during the mid-Pleistocene, a good example of insular gigantism. Neither are all pygmy Palaeoloxodon species the same size, or even the same shape. Instead they vary from island to island, the same as the other ex-megafauna. Some Maltese specimens indicate animals as tall as a grown man while the Spinagallo specimens indicate the smallest sizes. All these remains paint an incredible picture of a bizarre island ecosystem. Palaeoloxodon falconeri was thus not just a carbon copy of its continental giant kin. Rather it was its own unique animal, part of a fauna that would seem out of place anywhere else.
All in all these pint-sized elephants were unique, lost in their own world and unable to survive without it. It would be a while before climatic shifts would cool Europe, bringing temperatures down to freezing extremes. Some of the island dwarfs would survive the changes while some would not. A few enterprising pygmies would keep pulling through though, even to the point of near survival past the end of their era. These little pioneers would leave bones so fresh that archaic civilizations would one day include them in their mythologies many millennia later. It would be but a reminder of a time when the Greek islands were crawling with miniscule elephants no higher than a grown man’s waist.
Vasika
Udurawane
Writer
