The adult cattle egret has few predators, but birds or mammals may raid its nests, and chicks may be lost to starvation, calcium deficiency, or disturbance from other large birds. This species maintains a special relationship with cattle, which extends to other large grazing mammals; wider human farming is believed to be a major cause of their suddenly expanded range. The cattle egret removes ticks and flies from cattle and consumes them. They often accompany cattle or other large mammals, catching insect and small vertebrate prey disturbed by these animals.
Elephants can sleep both standing up and lying down. However, researchers have discovered that elephants in captivity tend to sleep more lying down than elephants in the wild. Elephants in the wild sleep more time standing up because it is easier for them to move. Since elephants are so large, it takes them much longer to get up. To protect one another from potential dangers, a herd of wild elephants sleeps in groups. Typically, one group of elephants will sleep while another group of elephants stays awake. The elephants that remain awake will watch for danger and warn the sleeping elephants of any potential dangers.
Rhino horn is used in Traditional Chinese Medicine, but increasingly common is its use as a status symbol to display success and wealth. Rhino horns are similar in structure to horses’ hooves, turtle beaks, and cockatoo bills. They are made of keratin – in rhinoceros horn, it is chemically complex and contains large quantities of sulfur-containing amino acids, particularly cysteine, as well as tyrosine, histidine, lysine, and arginine, and the salts calcium carbonate and calcium phosphate.