Palaeoloxodon falconeri

Palaeoloxodon falconeri derives from the 4 metre tall straight-tusked elephant (P. antiquus), which arrived in Europe approximately 800,000 years ago. The oldest radiometrically dated fossils of Palaeoloxodon on Sicily date to around 500,000 years ago while the ones found in Għar Dalam on Malta date to around 450,000 years ago. P. falconeri's ancestors most likely reached Sicily from the Italian mainland, likely via a series of islands that now form part of the southern Calabrian peninsula.[1] The chronology of the species compared to that of the larger endemic species of Palaeoloxodon on Sicily, the 2 m (6.6 ft) tall Palaeoloxodon mnaidriensis, is somewhat uncertain. It is generally thought that P. falconeri is the earlier species dating to the Middle Pleistocene, and that P. mnaidriensis descends from a separate late Middle Pleistocene colonisation of the island by P. antiquus.[2][1] P. falconeri also occurs on Malta, but is generally shorter making it a possible subspecies. It likely dispersed to Malta from Sicily during episodes of low sea level.[1]

In 1867, George Busk had proposed the species Elephas falconeri for many of the smallest molars selected from the material originally ascribed by Hugh Falconer to Palaeoloxodon melitensis for the Maltese dwarf elephant, a possible subspecies of P. falconeri.[3][4] The species Elephas/Palaeoloxodon melitensis, formerly considered a distinct species, is now considered a synonym of P. falconeri.[5]

Size comparison of Palaeoloxon falconeri compared to a human

This island-bound elephant is considered to be an example of insular dwarfism. In a 2015 study a composite adult male specimen MPUR/V n1 was estimated to measure 96.5 cm (3 ft 2.0 in) in shoulder height about 305 kg (672 lb) in weight, a composite adult female specimen MPUR/V n2 80 cm (2 ft 7.5 in) in shoulder height and about 168 kg (370 lb) in weight, and a composite newborn male specimen MPUR/V n3 33 cm (1 ft 1.0 in) in shoulder height and about 6.7 kg (15 lb) in weight.[6] A later 2019 volumetric study revised the weight estimates for the adult male and adult female to about 250 kg (550 lb) and 150.5 kg (332 lb) respectively. The newborn male of the species was estimated in the same study to weigh 7.8 kg (17 lb).[5] Female members of the species were tuskless.[1] Histology demonstrates that despite their small size, individuals of P. falconeri grew very slowly, reaching maturity at around 15 years of age, with some individuals reaching a lifespan of 68 years, comparable to full-sized elephants.[7] Dental microwear suggests that P. falconeri was a mixed feeder (both browsing and grazing).[8]

Sicily and Malta during the time of P. falconeri exhibited a depauperate fauna, with the only other mammal species on the islands being the cat-sized giant dormouse Leithia as well as the giant dormouse Maltamys, the otter Nesolutra, and an extinct species of shrew belonging to Crocidura.[9]