Marine Mammals Kingdom: Animalia Phylum: Chordata Class: Mammalia

Characteristics Mammals went from land to sea 50 million years ago. Their bodies have adapted to swimming and diving rather than running/jumping on land Only produce a few well cared for young Mammals are 1.Air breathing 2.Live birth, embryo receives nutrients through placenta 3.Warm blooded 4.Have mammary glands produce milk for young 5.Have hair at some point in their lives

Breathing Blowhole takes air to lungs Toothed whales have 1 nostril Baleen whales have 2 nostrils

Swimming Large body size- streamline shapes Tail flukes and hind flippers propel them through water

Blubber Mammals are endothermic (warm blooded) Blubber- used to keep them warm Over 60cm thick, traps heat.

Communication & Echolocation Well developed brains, very intelligent Communicates using clicks & sounds through the melon. – Use the reflected sound to determine size, shape and density. Songs produced by the Beluga & Humpback whales

Brain is larger in relation Comparison of Vertebrate Brains- Brain is larger in relation to body size & more complex compared to other vertebrates This allows more storage & processing of information

class Mammalia order Pinnipedia (Seals, Sea Lions & Walruses) order Carnivora (Sea Otters) order Sirenia (Manatees & Dugongs) order Cetacea (Whales, Dolphins & Porpoises)

Only marine member of the order Carnivora (exception- Polar bear)Only marine member of the order Carnivora (exception- Polar bear) Lacks a layer of blubber, has dense fur for insulationLacks a layer of blubber, has dense fur for insulation Almost killed to extinction in 1911Almost killed to extinction in 1911

Cetaceans (Cetus: greek for whale) Largest group (90 species) Experienced complete transition to aquatic life Breathe through one single or double blowhole /video/player/animals/mammals- animals/dolphins-and- porpoises/dolphin-pink-river.html /video/player/animals/mammals- animals/dolphins-and- porpoises/dolphin-pink-river.html All marine except a few species of dolphins Cetaceans divided into 2 groups: – Toothless, filter feeding – Toothed, carnivorous River Dolphin

Toothless Whales- have two blowholes Baleen is rows of flexible, fibrous plates that hang from the upper jaws. Made of keratin (similar to hair & nails) Hanging from the plates are bristles that overlap and form a dense mat This filters out the food from the water that the whale takes in 13 species- Blue whale is largest (M-80ft/ F-110ft) Baleen used for boning in corsets Suborder: Mysticeti (Baleen whales)

Rorquals Whales that have an expanding throat (accordion like) Ex. blue whale, fin whale, minke whale, & humpback whale Blue Whale

Suborder: Odontoceti, (toothed whales) Most are dolphins & porpoises Largest toothed whale is the sperm whale-Now the most numerous Pressures from whaling, drowning in nets are impacting all populations

Humpback Whale spout  Large whales will have a visible spout when they blow air out of blowhole  This is the condensation of their warm breath hitting the cooler air  The height & angle can help ID a whale at a distance (Blue Whale ft high) whaling/blows/spouts.html