Mammals share three traits no other group has: mammary glands with which they feed their young, hair — though in whales and dolphins it is reduced to a few bristles on the foetus — and a middle ear of three small bones. Beyond that they are an extraordinarily diverse group, with forms ranging from a two-gram bat to the blue whale, and they have colonised the ground, the trees, the world below ground, the air and the open sea. It is the class that receives the most conservation attention, and also the one whose status is best known.
Species
Natural phenomena
Fruit bat migration at KasankaBest time to see jaguars in the PantanalNarwhal migration to Baffin BayGreat Migration: the Mara River crossingElephant seal breeding season in CaliforniaGrey whales calving in the lagoons of Baja California
Dry season in the Okavango
Great Migration: calving season at Ndutu
Humpback whale season in Hawaii
Iberian lynx mating season
Brown bears fishing for salmon at Brooks Falls
Humpback whale season in Tonga
Orcas and whales following the herring in the Norwegian fjords
Southern right whales at Peninsula Valdes
Red deer rut in Scotland
Blue whale watching in Sri Lanka
Snow leopard mating season
Urban bat colony under Congress Avenue Bridge
Walrus haulout on Round Island
North Atlantic right whales feeding in Cape Cod Bay
Snow monkeys in the Jigokudani hot springs
Best time to see giant otters in the Pantanal
Best time to see Amazon river dolphins
The Iberian red deer rut
Polar bear gathering at Churchill
Summer beluga gathering in the Churchill River estuary
Humpback whales in Samana Bay
Southern right whales at Hermanus
Zebra migration from the Chobe to Nxai Pan
Manatee wintering at Crystal River
Intentional stranding of killer whales at Peninsula Valdes
Grey seal pupping at Donna Nook
The Humpback Highway on Australia's east coast
Humpback whales on the Colombian Pacific coast
Resident sperm whales in the Kaikoura Canyon
Humpback whales off Sainte-Marie Island
Elephant concentrations at the Hwange waterholes
Cape fur seal pupping at Cape Cross
Blue whale feeding in the Gulf of Corcovado
Calving and migration of the Porcupine caribou herd
