Shrews are violent animals despite their maximum length of six inches. Despite having over 300 different species, the largest living species, the Asian house shrew, is only about six inches long from nose to tail tips. The size of these mammals make them prey to a lot of animals. However, millions of years ago, Italy had an ancestor of these animals that was once large enough to defend itself. This article introduces the ancient “Terror Shrew” that once roamed Italy.

Meet the “Terror Shrew”: Deinogalerix

Deinogalerix can be translated to mean “terror hedgehog.” According to reports, Deinogalerix lived between the Oligocene and late Miocene Periods about 7 to 10 million years ago. Over the years, there have been seven named species of this extinct genus, which include Deinogalerix masinii, Deinogalerix freudenthali, Deinogalerix minor, Deinogalerix samniticus, Deinogalerix brevirostris, Deinogalerix intermedius, and Deinogalerix koenigswaldi. The oldest of the species, Deinogalerix masinii, was also the smallest of the seven. It was one and half times the size of the modern-day hedgehog, reaching up to 1.5 feet in length. The largest, Deinogalerix koenigswaldi, was about two feet long, and its jaws measured about eight inches, making it close to the size of a cat.

What Did Deinogalerix Look Like?

Deinogalerix looked similar to hedgehogs. Like hedgehogs, Deinogalerix was a hairy mammal with short legs and sharp teeth, common with members of Insectivora. However, Deinogalerix had elongated snouts and was larger in size. The head of Deinogalerix accounted for more than a third of its body length. Like other insectivores, their tibia and fibula are fused near the ankle.

Was Deinogalerix Venomous?

Shrews are one of the most venomous mammals worldwide. The venom in the saliva of these little animals can paralyze threats such as frogs and fish, both of which weigh more than shrews. According to the Maryland Department of Natural Resources, the venom in the saliva of the northern short-tailed shrew is not deadly to humans and large wildlife. However, they can inflict sharp bites if handled.     Little is known about Deinogalerix’s saliva since the discovery of their fossil remains only indicated their existence and base of study. However, given their relatively larger size, Deinogalerix might not have needed venom to catch their prey. According to reports, they might have relied more on capturing prey between their long jaws.

Diet: What Did Deinogalerix Eat?

Deinogalerix ate insects and small invertebrates. These insectivores fed on dragonflies, snails, and beetles. Given their large sizes and well-developed incisors, some believed these animals would have attempted to prey on small mammals and birds. However, it was concluded that Deinogalerix could have been scavengers, given their size, which would have made them slower than modern-day hedgehogs.   

Dentition of Deinogalerix

According to reports, Deinogalerix koenigswaldi had symmetrical teeth that included two incisors, one canine, four premolars, and three molars. Therefore, it can be assumed that these large mammals had about 40 teeth in their mouths. This is not far-fetched since their close relatives, the hedgehogs, have between 34-44 teeth.  

Habitat: Where It Lived

Deinogalerix was endemic to the southeastern part of Italy. These giant shrews lived on Gargano Island, which has aged into the Gargano Peninsula in the present day. According to debates, Deinogalerix would have migrated to the island about 10 million years ago.

Evolution of Deinogalerix

According to a journal, Deinogalerix reproduced rapidly on Gargano Island and evolved to larger sizes. This is typical for insular mammals, which often develop differently compared to their counterparts on the mainland. Mammals on the mainland often compete with other animals for food and adapt to protect themselves from predators. Some small mammals like shrews are venomous, release foul odors to discourage predators, or are quite speedy on their little legs. Large mammals are hardly found on islands, as they cannot swim to these isolated areas. Deinogalerix developed newer and necessary adaptions without predators and competition and grew to larger sizes on the Old Italian Island.  

Predators: What Animals Preyed on Deinogalerix?

While it is believed that reptiles and birds of prey could also have existed in the time that Deinogalerix did, they were either unsuitable for hunting Deinogalerix or uncommon. The giant mammals might not have been able to evolve to larger sizes if they had many predators.

When and Where Was Deinogalerix Discovered?

According to science reports, the Italian “Terror Shrew” was first discovered in 1972. The first skeleton found was an almost complete skeleton of the Deinogalerix koenigswaldi, which had a skull of about 21 cm (8.3 inches). In 1980, four other species of Deinogalerix were added. At first, Deinogalerix freudenthali and Deinogalerix minor were thought to be the species’ smallest and most probable ancestors. However, that was until the discovery of Deinogalerix masinii.     

Deinogalerix vs. Largest Living Rodent

According to World Atlas, the largest living rodent is the South American capybara which can grow over four feet long and weigh as much as 145 pounds. Rodents are among the most diverse species in the world, with over 1,500 species ranging from as little as a mouse to as big as guinea pigs and porcupines. Capybaras feed on grass, grains, and fruits and are oddly adept swimmers. Deinogalerix, while larger than hedgehogs and shrews, was smaller than the largest capybara. Capybaras are twice the lengths of the largest Deinogalerix species and would have weighed more. Deinogalerix is closer in size to beavers than to the larger capybara. 

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