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منذ 13 ساعة نشر في ٢٠٢٦/٠٨/٢٦ م

Compared to lynx and wolves, the wolverine has a low reproduction rate. A female wolverine does not give birth to her first litter until she is three or four years old. After that, she usually gives birth only every other year. The female is the sole carer for the young kits, which stay with their mother for about a year before moving on to their own territory.

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منذ 2 أيام نشر في ٢٠٢٦/٠٨/٢٥ م

The wolverine is found throughout the tundra and taiga forest belts of the northern hemisphere, in Europe, Asia and North America. In Europe, it is only found in Russia, Finland and Scandinavia. It is mainly found in mountain ranges, as well as in woodlands and on marshland. It is a shy creature, preferring large, preferably uninhabited areas with unspoilt nature.

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منذ 3 أيام نشر في ٢٠٢٦/٠٨/٢٤ م

When the hunting conditions are good – with hard snow crust, or loose snow that supports its broad paws while reindeer sink down – the wolverine can bring down large numbers of prey which it dismembers, hides and eats later. Good hunting conditions allow the wolverine to kill many reindeer, which naturally creates conflicts with humans. The wolverine lives alone and can roam for long distances, often following the movements of the reindeer.

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منذ 5 أيام نشر في ٢٠٢٦/٠٨/٢٢ م

The shy wolverine has a reputation for being both gluttonous and cruel. Many people think it hunts just because it enjoys killing, but the wolverine is only a mediocre hunter. It mainly eats carrion, in other words dead animals or animals that other predators have already killed.

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منذ 6 أيام نشر في ٢٠٢٦/٠٨/٢١ م

It moves with a distinctive jogging gallop. The wolverine is fast, running at speeds of up to 45 kilometres per hour. It uses its large paws to run on top of the snow without sinking. A healthy wolverine can run for sixty kilometres without resting.

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منذ 1 أسابيع نشر في ٢٠٢٦/٠٨/١٩ م

The wolverine has dark brown fur and a small head with small ears. It has short legs, a long bushy tail and large paws in relation to its body size, allowing it to run on top of the snow without sinking. An adult male wolverine weighs about 16 kilograms, while an adult female weighs about 10 kilograms.

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منذ 1 أسابيع نشر في ٢٠٢٦/٠٨/١٨ م

The wolverine is a member of the weasel family and lives in northern Sweden. It is a predator that hunts for its food, but often has to make do with left-overs from the prey of animals such as lynx, wolves and bears.

The wolverine is the world’s largest land-dwelling mustelid. It is a solitary animal, meaning that it lives alone, and in Sweden it is found almost exclusively in reindeer herding areas.

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منذ 1 أسابيع نشر في ٢٠٢٦/٠٨/١٧ م

As part of the soil ecosystem, land planarians feed mainly on other invertebrates, such as earthworms, snails, slugs, nemerteans, velvet worms, woodlice, millipedes, insects and arachnids. Some may even feed on other land planarians.

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منذ 2 أسابيع نشر في ٢٠٢٦/٠٨/١٥ م

The pharynx is specializes as a penetration organ for those planarians that feed on arthropods; or as a grasping organ for those planarians that feed on other soft bodied invertebrates such as earthworms. All geoplanidae pharynxes are equipped with glandular secretions that externally digest and dissolve their prey.

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منذ 2 أسابيع نشر في ٢٠٢٦/٠٨/١٤ م

Land planarians are carnivorous and most species are active predators, but some are mainly scavengers.

All planarians feed through a muscular and eversible pharynx located slightly posteriorly to the middle of the body length and opening through a ventral mouth. The pharynx is an extensible tube-like organ bearing a complex muscular coat.

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منذ 2 أسابيع نشر في ٢٠٢٦/٠٨/١٣ م

During unfavorable conditions, such as dry seasons, land planarians tend to seek shelter by burrowing in the soil or building a cyst composed of soil particles united by mucus.

Some species are well adapted to human-disturbed environments and many of those have been introduced in areas outside of their native range. In some localities, such as the United Kingdom, the number of introduced land planarian species greatly surpass the number of described native species.

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منذ 2 أسابيع نشر في ٢٠٢٦/٠٨/١٢ م

Most species of land planarians live at the soil of forests, especially in the leaf litter layer, but some may inhabit galleries constructed by other invertebrates or be found on vegetation, such as bromeliads.

Despite being sensitive to dehydration, some species are well adapted to considerably dry environments, such as savannas.

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منذ 2 أسابيع نشر في ٢٠٢٦/٠٨/١١ م

Although there are over 830 known species of Geoplanidae in the world, the diversity of land planarians is still poorly known.

The highest diversity occurs in tropical forests in South America, Asia and Australia. Europe and North America are relatively species-poor, while the diversity of Africa may be as high as that of other tropical regions, but is highly understudied.

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منذ 2 أسابيع نشر في ٢٠٢٦/٠٨/١٠ م

Contrary to aquatic planarians, land planarians do not have a distinct brain, i.e., there is no clear frontal cluster of nerve cells other than the ventral nerve plate.

The family Geoplanidae is composed of five subfamilies:
Bipaliinae
Geoplaninae
Microplaninae
Rhynchodeminae
Timyminae

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منذ 3 أسابيع نشر في ٢٠٢٦/٠٨/٠٧ م

The nervous system of land planarians has the longitudinal nerve cords reduced to one ventral pair that is located much deeper in the body than in other triclads. These ventral cords are usually connected by many comissures, so that they fuse into a single ventral nerve plate.

Additionally, land planarians have a highly developed ventral nerve plexus just below the epidermis that is probably associated to the presence of a creeping sole.

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منذ 3 أسابيع نشر في ٢٠٢٦/٠٨/٠٦ م

The epidermis of land planarians is composed by a simple epithelium of cubic or columnar cells. The cells are ciliated only on a ventral region, called creeping sole, which the animal uses to glide over surfaces.

Numerous secretory cells open throughout the epidermis, the most characteristic ones being the rhabditogen cells, which produce a secretion in the form of small rod-like structures, the rhabdites. Rhabditogen cells are very numerous on the dorsal epidermis.

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منذ 3 أسابيع نشر في ٢٠٢٦/٠٨/٠٥ م

The most distinguishing feature that characterizes land planarians is the presence of a creeping sole, a highly ciliated region on the ventral epidermis that helps them to creep over the substrate.

The creeping sole may be wide and flat, occupying most of the ventral surface, or narrow and pronounced, being easily distinguished from the rest of the ventral surface.

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منذ 3 أسابيع نشر في ٢٠٢٦/٠٨/٠٤ م

At first they may be confused with slugs or leeches, but they lack the anterior tentacles of slugs and the segmentation of leeches. Their size vary greatly, from a few millimeters in length to about one metre.

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منذ 3 أسابيع نشر في ٢٠٢٦/٠٨/٠٣ م

Land planarians are distinguished from their marine and freshwater relatives by their terrestrial habits, as well as by morphological distinctions. Some species have dull colors, including shades of brown and grey, that make them inconspicuous in their environment, but most species are marked by very colorful patterns.

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منذ 3 أسابيع نشر في ٢٠٢٦/٠٨/٠٢ م

At the other extreme, one species in this family, Platydemus manokwari has become an invasive species in both disturbed and wild habitats in the Pacific Islands, and has damaged the endemic land snail fauna. This species has been found in Europe (France) in 2013 for the first time, and in 2015 in New Caledonia, Wallis and Futuna Islands, Singapore, Solomon Islands, Puerto Rico (first record in the Caribbean), and Florida, USA.

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منذ 4 أسابيع نشر في ٢٠٢٦/٠٧/٣٠ م

Because of their strict ecological requirements, some species have been proposed as indicators of the conservation state of their habitats.

They are generally animals with low vagility (dispersal ability) and with very specific habitat requirements, so they can be also used to accurately determine the distribution of biogeographic realms.

Today the fauna of these animals is being studied to select conservation priorities in the Atlantic rainforest in Brazil.

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منذ 4 أسابيع نشر في ٢٠٢٦/٠٧/٢٩ م

Geoplanidae is a family of flatworms known commonly as land planarians or land flatworms.
These flatworms are mainly predators of other invertebrates, which they hunt, attack and capture using physical force and the adhesive and digestive properties of their mucus.
They lack water-retaining mechanisms and are therefore very sensitive to humidity variations of their environment.

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منذ 4 أسابيع نشر في ٢٠٢٦/٠٧/٢٨ م

Various conservation initiatives are being attempted around the world. The Chinese giant salamander, at 1.8 m (6 ft) the largest amphibian in the world, is critically endangered, as it is collected for food and for use in traditional Chinese medicine. An environmental education program is being undertaken to encourage sustainable management of wild populations in the Qinling Mountains and captive breeding programs have been set up.

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منذ 1 شهور نشر في ٢٠٢٦/٠٧/٢٧ م

Other larvae, especially in permanent pools and warmer climates, may not undergo metamorphosis until fully adult in size. Other populations in colder climates may not metamorphose at all, and become mature for mating while in their larval forms. Neoteny allows the species to survive even when the terrestrial environment is too harsh for the adults to thrive on land.

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