The young cubs or pups of predators are very entertaining to watch as they chase one another around, harass and attack other members of the group, and stalk and pounce on inanimate objects. This playfulness is nature’s way of ensuring that the youngsters develop muscles and dexterity, practise and hone reactions and techniques, and gain confidence in their abilities – all of which will come into use when they learn to hunt. Initially, before they accompany the adults on hunts and have the chance to learn by observation, they rely on the instinct to pursue movement. In all predators the urge to stalk, hunt or chase a moving object is innate and entirely removed from the urge to eat. At this stage, and as they mature, youngsters will stalk, chase and pounce on one another, their parents, insects, vegetation moving in the wind, tortoises, the flicking ear or tail of an adult, or anything else that is moving and offers a challenge. This instinctive urge to subdue anything that moves close to them is vital for later survival. Once they start to observe hunts in action, they mimic biting techniques on one another or unamused adults. These skills develop rapidly as they get a chance to participate in the hunt. Playfulness, which varies according to species, is also a vital form of bonding between siblings and adults.

  The young of herbivores generally learn by observation and develop defence and fighting skills through play-fighting. In most species, competition between siblings does not lead to injury or death, but in some species aggression leading to death of one or more babies is the norm.

  Siblicide is the behaviour of siblings killing each other – usually one dominant animal killing one or two siblings. It was formerly called cainism, the name derived from the biblical story where Cain killed his brother Abel. It is thought to be a way of one sibling proving its superiority and survival capabilities for not only itself but, more importantly, for the species as a whole. Once the ‘test’ has been passed and the sibling (or competitor) removed from the equation, then all parental care and energy is bestowed upon only the one individual. Because this places less pressure on the parents (in terms of supplying food and having time to teach the youngster survival skills), the chances of the youngster being successfully raised with the necessary life skills are greatly improved.

  In spotted hyena, competition is very intense, and because they have a matriarchal society, this intensity is greatest between two sisters (they usually only have two cubs). One sister invariably kills the other in the quest for dominance. Hyena cubs or unusual carnivores in that they are born with fully erupted front teeth (incisors and canines), so they have some serious weapons and powerful jaws from day one with which to attack siblings. Siblicide is common in many birds of prey (raptors) and other large birds such as ground hornbills.

  In mammals, this behaviour tends to be active siblicide where the stronger and more dominant sibling physically attacks the weakest sibling, directly resulting in its death through injury. This is opposed to passive siblicide where there are food shortages and the dominant sibling steals what is offered – indirectly leading to death of the weaker sibling through starvation. This is far more common in birds where food is being brought back to the nest and the bigger and older chick, having hatched a few days earlier, is easily able to dominate the food source. In mammals, however, there is firstly no initial marked size differential between siblings as both are born at the same time, and secondly, they drink milk so there is no food being brought back to fight over.

  As is the case with spotted hyena, there are two teats, and therefore a minimal chance for the one sibling to dominate the food source. They can, however, try to prevent their siblings getting to the teat area. As a result you will usually see spotted hyena siblings suckling with one at the belly area and the other accessing a nipple from between the hind legs of the mother.

Excerpts from ‘Beat about the Bush – Mammals and Birds’ by Trevor Carnaby, Published by Jacana Media, Second Edition reprint 2018.