Elephants are intelligent and vigorous creatures that have evolved in an extensive and complex physical and social environment. Adapted to vast areas, the continuous larger and smaller scale movements related to the search for food, water, companions and mates are essential for elephant well being.
Elephants require sustained, biologically relevant activities for body and mind. We are obliged to account for this and the consequent necessity of large space for elephants in the wild and sufficient space in captivity.
- Over the course of 60 million years the proboscids as a taxonomic group have generally evolved to become very large, though the reverse process of dwarfing has also occurred when they have been confined to islands. Elephants are the biggest of the earth’s extant land mammals and require large quantities of food and water to survive.
- To meet the energetic requirements associated with large body size the elephants have evolved unique physical and behavioral traits to travel and search over great distances to locate widely dispersed food, water and mates. Adaptations include a highly mobile trunk, a pharyngeal pouch, pillar-like legs and cushioned feet, production and detection of powerful low-frequency sounds that travel acoustically and seismically, acute sense of small and long-term spatial and social memory.
- Elephants are among a very few mammal species whose evolution includes the continuation of physical growth long after sexual maturation and even into late maturity.
- Sexual dimorphism in body size is pronounced in elephants. Fully-grown male elephants are on average up to 30% taller and up to double the weight of fully-grown female elephants resulting in distinct differences in energetic requirements between males and females. Elephants have solved this dimorphic dilemma by the partial segregation of male and female societies and the utilization of different habitats.
- Free-living elephants are on the move for about twenty hours of the day, actively engaged in foraging, exploring, socializing and searching for conspecifics. Activity budgets and patterns vary according to age, sex, reproductive states, season and habitat. In their natural habitat they spend the majority of their time (>85%) engaged in active physical pursuits (feeding, moving while feeding, walking, interacting, comfort activities, drinking) and very little time (<15%)standing in one place or resting. Adult elephants usually rest standing up during the day, but at night they usually rest lying down for a couple of hours and elephants in their natural habitat usually walk between five and 20 km per day.
- Elephant home ranges vary from 100 sq km to 11,000 sq km. Smaller elephant home ranges are generally associated with habitats of high resource availability, though this may also reflect geographical confinement.
- Even within a single habitat and population, home range size varies considerably from individual to individual, reflecting personal and family preferences, historical patterns, seasonal variation, and social relationships.
- In the wild elephants are vigorous animals, perpetually active in mind and body. Everything an elephant does is an intellectual challenge: locating and manipulating a wide variety of food items; discriminating between the individual scents, voices and appearances of familiar and unfamiliar individuals, including friends and foes, relatives and non-relatives, higher ranking and lower ranking competitors, friendly and unfriendly heterospecifics; remembering the location of water during a drought; searching for potential mates; deciding where to go, who to go with, who to join and who to avoid. The overall lack of biologically relevant mental stimulation and physical activity is a source of suffering in captive elephants.