Mark MacEwen / Banded mongoose (Mungos mungo) juvenile sleeping on adult 'escort', Queen Elizabeth National Park, Mweya Peninsula, Uganda, Africa.

Diane McAllister / Japanese Macaque (Macaca fuscata) juvenile riding on its mother's back, along snow trail in Jigokudani, Japan.

Mark MacEwen / Broad snouted caiman (Caiman latirostris) baby carried in mother's mouth from the nest, Sante Fe, Argentina, February

Hiroya Minakuchi / Orca (Orcinus orca) mother and newborn baby with escort, Sea World, Kamogawa, Japan

Tony Wu / Humpback whale (Megaptera novaeangliae australis), male calf resting beneath his mother. Male escort visible in background. Vava'u, Tonga, South Pacific.

Tony Wu / Humpback whale (Megaptera novaeangliae) rear view of males escort, with adult female and male calf in the background. Vava'u, Tonga, South Pacific.

Tony Wu / Humpback whale (Megaptera novaeangliae) adult female in foreground, with her male calf and their escort behind her. Vava'u, Tonga, South Pacific.

Tony Wu / Humpback whale (Megaptera novaeangliae) male calf relaxing with his mother and an escort whale in the background. Vava'u, Tonga, South Pacific.

Tony Wu / Humpback whale (Megaptera novangliaea) male escort body blocking another male in pursuit of female, part of competitive group heat run, Vava'u, Tonga, South Pacific

Tony Wu / Humpback whale (Megaptera novaeangliae) female calf tail slapping at the ocean surface, playing with her mum and an escort, Vava'u, Tonga, South Pacific

Tony Wu / Humpback whale (Megaptera novaeangliae) male calf opening his mouth whilst playing with mother and escort, Vava'u, Tonga, South Pacific

Tony Wu / Humpback whale (Megaptera novaeangliae) male escort breaching, Vava'u, Tonga, South Pacific