It is estimated that rhinos have roamed the planet for around 50 million years. These ancient creatures have braved ice ages, predators and habitat loss. However, they now face the threat of extinction at the hands of poachers who slaughter rhinos for their horns which are then traded on the black market in Asia. Of the five species of rhinos, White, Black, Greater-One horned, Sumatran and Javan, all are listed on the IUCN Red List of Endangered Species.

As we recognise World Rhino Day on September 22, 2017, we take a moment to reflect on this wonderfully unique and fascinating species. With many organisations working to build a future for rhinos, consider showing your support for a rhino related cause.

Here are some fascinating facts about rhinos that you may not have known.

1. The White Rhino is the second largest mammal on earth.

2. A group of rhinos is called a crash.

3. A rhino horn never stops growing and can grow between 2–6cm in a year.

4. Rhinos shape their own horns by rubbing against hard surfaces.

5. You will sometimes see a rhino eating soil. This adds minerals to their diet.

6. Rhinos enjoy wallowing in mud both to keep cool and to remove parasites from their skin.

7. Rhinos have territories of up to 14km and require large amounts of water each day. If a bull does not have water in his territory, rival bulls will allow him to enter theirs to drink water only, so long as he shows submissive behaviour.

8. Rhino bulls are fiercely territorial; they mark their territory by patrolling well-used paths, spraying their urine backward onto bushes, creating visible scrape marks with their feet and kicking dung after defecating to leave their scent.

10. Rhinos can mate for a full 30 minutes. Once a cow is identified, a bull will go to great lengths to keep her on his turf and will often chase her round. Courtship can last for between 14–20 days.

Source: Game Ranger in a Backpack Megan Emmet and Sean Patrick