Do elephants need to sweat?

Abstract

An adequate rate of evaporative water loss is considered es• sential for the maintenance of thermal balance in the elephant in warm climatic conditions. Histological studies have failed to reveal the existence of sweat glands in elephant skin. Trans• epidermal water•loss rate has been measured and shown to be sufficiently high for possible thermal needs. The structure of elephant skin and the behaviour of elephants are seen to con• tribute towards maintaining skin permeability and the necessary level of transepidermal water loss.

Body temperature daily rhythm adaptations in African savanna elephants (Loxodonta africana)

“…Although behavioural thermoregulation is well documented for savanna elephants (e.g. [19] and [20]), due to the difficulty of obtaining physiological parameters, little is known about the T b of elephants and nothing known of their T b daily rhythms.…”

“…Elephants do not possess sweat glands but cool themselves using transepidermal water loss [19]. They also often make use of free standing water in which to wallow and bathe [19] and their large ears act as thermal windows [20]. In addition, recent work has shown that during the hot dry season in Zambia, free-ranging elephants select shaded habitats in the heat of the day and select landscapes that facilitate heat loss during the cool evenings [21].…”

“…In these habitats, water sources are often sparse and peak ambient temperatures may reach up to 50 °C at certain times of the year [18] with hot dry season daily fluctuations in some regions ranging from approximately 8 °C at night to well over 40 °C during the day (A.A Kinahan unpublished data). Elephants do not possess sweat glands but cool themselves using transepidermal water loss [19]. They also often make use of free standing water in which to wallow and bathe [19] and their large ears act as thermal windows [20].…”

The pitfalls of ignoring behaviour when quantifying habitat selection

“…In the dry season, African savanna elephants (Loxodonta africana) must fulfil competing physiological requirements. For instance, individuals must visit water regularly to meet several physiological needs (Wright & Luck, 1984;Harris et al, 2008;Loarie et al, 2009). However, areas near water often are nutritionally depleted in the dry season (de Beer et al, 2006), so elephants travel away from water in search of forage.…”

Passive external transport of freshwater invertebrates by elephant and other mud-wallowing mammals in an African savannah habitat

“…, 2008c). Additionally, many African mammal species, such as warthog, rhinoceros, buffalo and elephant frequently engage in wallowing, purposely covering their skin with mud from shallow freshwater habitats (Wright & Luck, 1984; Owen‐Smith, 1992), an activity that could potentially result in the attachment of large numbers of propagules present in the sediment (Vanschoenwinkel et al. , 2008c).…”