Chordate Zoology - Textbook - Y. V. Tsaryk - 2013

Chapter 5. SUPERCLASS TETRAPODS (TERRESTRIAL VERTEBRATES) TETRAPODA, seu QUADRIPEDA.

ANAMNIOTES (ANAMNIA) AND AMNIOTES (AMNIOTA)

5.4. CLASS MAMMALS, MAMMALIA, seu THERIA

5.4.4. Systematics and Characteristics of Representatives of the Main Orders of the Class Mammalia

5.4.4.2. Subclass Theria

5.4.4.2.4. Order Insectivora (Soriciformes)

These are small to medium-sized animals (body length 3.5–44.0 cm) of primitive Structure. The pelage is short and soft, or the body is covered with spines (hedgehogs). The Skull is elongated; the auditory bullae are underdeveloped. In the Brain, the olfactory lobes are highly developed, and the cerebral hemispheres are almost smooth. Activity is predominantly nocturnal, though some species are active around the clock. They give birth to 6–14 young and are polygamous. Moles and, historically, desmans are commercially hunted species; shrews and hedgehogs destroy many agricultural pests. They are widely distributed, except in Australia, Antarctica, and most of South America. The order comprises seven families (428 species). They are known from Late Cretaceous deposits.

The hedgehog family, Erinaceidae, comprises 24 species (body length 10–44 cm). The snout is elongated and pointed; the DORSAL SIDE OF the body is covered with spines, or with coarse Hair in gymnures; they are capable of rolling into a ball. They inhabit forests, cultivated landscapes, steppes, and deserts. They are omnivorous, though they prefer animal food. They inhabit Africa and Eurasia (north to the tree line). In the fauna of Ukraine, the northern white-breasted hedgehog Erinaceus roumanicus is widespread, while the long-eared hedgehog Hemiechinus auritus occurs in the steppes of eastern Ukraine (Fig. 5.74, 10). Modern systematics places the hedgehog family in a separate order, Erinaceomorpha. However, V. I. Pavlinov (2003) considers the hedgehog family, along with shrews and moles, within a single order of insectivores, Eulipotyphla.

The mole family, Talpidae, includes 46 species (body length 5–21 cm). The digits have long claws; the snout is elongated, the eyes are tiny (in some species, covered by Skin), and external ears are small or absent. Moles and desmans possess valuable fur. They inhabit diverse landscapes; most species live and feed in burrows, some hunt On the surface, and some are excellent swimmers. In Eurasia, they are distributed north to 63° N and south to the Mediterranean Sea and Southeast Asia; in North America, they range from southern Canada to Mexico. The European mole Talpa europaea is widespread in Ukraine; the Russian desman Desmana moschata is currently an extremely rare species in Ukraine (Fig. 5.74, 11).

The tenrec family, Tenrecidae, unites 34 species. They inhabit Madagascar and the Comoro Islands, where they have radiated into A number of forms externally resembling hedgehogs, shrews, muskrats, and even otters. Apparently an ancient group, they are known from the Late Cretaceous.

The golden mole family, Chrysochloridae, inhabits Southern Africa; like our moles, they lead an underground lifestyle. The Hispaniolan solenodon Solenodon paradoxus (family Solenodontidae) lives in Haiti, while another species, Solenodon cubanus, is found in Cuba; these large shrew-like animals are nearly extinct. Modern systematics places the tenrec and golden mole families into a separate order, Afrosoricida.

The shrew family, Soricidae, consists of small-sized animals (length 3.5–18.0 cm) and comprises 376 species. They are widely distributed, except in polar regions, Australia, and southern South America. They inhabit diverse landscapes, including tundras and deserts, and ascend mountains up to 4,000 m above sea level. They feed on small animals and occasionally seeds. They are active around the clock, alternating short periods of feeding and Sleep. In winter, shrews exhibit a reduction in body size (including the skull), which can likely be explained as an adaptation to limited food supplies and the difficulty of obtaining it. This phenomenon of seasonal body size fluctuations was described by the Polish zoologist A. Dehnel and was later named Dehnel's phenomenon. In forest biocenoses of temperate zones, shrews play a significant role due to their Abundance and High Metabolic Rate. This family includes some of the smallest extant mammals, such as the tiny shrew Sorex minutissimus and others, weighing only 2–3 g. There are eight species in the fauna of Ukraine. Representatives include the common shrew Sorex araneus, the Eurasian Water shrew Neomys fodiens, and the bicolored shrew Crocidura leucodon.

The elephant shrew family, Macroscelididae, is distributed in Africa (15 species). Externally, they resemble jerboas, with hind limbs significantly longer than forelimbs (Fig. 5.74, 12).

They typically use both pairs of limbs, but during rapid running, they use only their hind limbs. They feed on insects, especially termites, as well as seeds and fruits. Modern taxonomists place this group of animals in a separate order, Macroscelidea, with the single family Macroscelididae.