Rhinoceros Horn Shrinkage

According to a British Ecological Society study, rhinoceroses horns may have shrunk over time.

Reasons for Horn Shrinkage

• Rhinos' horns, which are highly valued in some cultures, have long been hunted.
• The decreasing horn length across species over time, possibly due to hunting selective pressure and evolution.

Important Fact:

• Keratin, the main component of human hair and fingernails, is used to make rhino horns.

More on the Research

• The study discovered that the rate of horn length decline was highest in the critically endangered Sumatran rhino and lowest in the white rhino of Africa, which is the most common species both in the wild and in captivity.
• This observation corresponds to patterns observed in other animals, such as elephant tusk size and wild sheep horn length, which have been driven down by directional selection due to trophy hunting.

Rhinoceroses

• Rhinoceroses are large herbivorous mammals distinguished by their distinctive horned snouts.
• The term "rhinoceros" is derived from the Greek words "rhino" (nose) and "ceros" (horn).
• There are five rhino species and 11 subspecies; some have two horns, while others only have one.
• White rhinos and black rhinos can be found in the grasslands and floodplains of eastern and southern Africa.
• Greater one-horned rhinos can be found in northern India and southern Nepal's swamps and rain forests.
• Sumatran and Javan rhinos can only be found in a few areas of Malaysian and Indonesian swamps and rainforests.

Threats:

• Loss and fragmentation of habitat

• Poaching (especially for their horns and hide) (especially for their horns and hide)
• Population density reduction
• Genetic diversity is dwindling.

The five species' conservation statuses are as follows:

• Javan rhinos (Rhinoceros sondaicus) are critically endangered, as are Sumatran rhinos (Dicerorhinus sumatrensis) and black rhinos (Diceros bicornis). White rhinos (Ceratotherium simum) are critically endangered.
• Greater One-Horned Rhinos (Rhinoceros unicornis) are endangered.

Rhinos in India

• Only the Greater One-Horned Rhino, also known as the Indian rhino, is found in India. It is the largest of the rhino species.
• Assam has the largest rhino population in India and had at least five rhino-bearing areas until the 1980s.
• It has a single black horn and a grey-brown hide with skin folds that distinguishes it.
• They primarily graze, eating almost entirely grasses as well as leaves, shrub and tree branches, fruit, and aquatic plants.

India's Conservation Efforts

• 2019 New Delhi Declaration on Asian Rhinos: India, Bhutan, Nepal, Indonesia, and Malaysia have all signed.
• The Ministry of Environment, Forestry, and Climate Change's National Rhino Conservation Strategy 2019 Project will create DNA profiles of all rhinos (MoEFCC).
• Vision 2020 for Indian Rhinos.
• Every year on September 22nd, World Rhino Day is observed.

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