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Unformatted text preview: Lecture Notes The Biology of Marine Mammals Spring 2010 Dr. Mike Heithaus Marine Sciences 361 Office Hours: Tue 1300-1630* *by appointment; I am also available by appointment at other times firstname.lastname@example.org (305) 919-5234 www.fiu.edu/~heithaus Goals for the course • Gain an appreciation for the evolution and diversity of marine mammals • Gain a basic understanding of the physiology, population biology, ecology, and behavior of marine mammals • Learn the theory relevant to these areas of biology, especially ecology and behavior • Begin to explore the primary scientific literature and learn research techniques Course structure • Lectures: T,Th 0930 • Grading – 4 Exams – Participation in Class Discussions Succeeding in this class • Read the assignments/papers that are assigned – you will be responsible for some material outside of lecture notes! • Don’t skip classes • Take good notes, and ask questions! • Make sure you understand your notes • Get help if you don’t understand something – Book, peers, me • Come talk to me! Marine Mammal Diversity and Zoogeography Marine Mammals • Any mammal that takes to the sea for part of its life • Polyphyletic group of ~120 species – Taking to the sea has evolved multiple times among mammals – at least 5-8 times Marine Mammal Diversity • Extant groups – Ceataceans – Sirineans – Pinnipeds – Sea Otter – Polar Bear • Extinct groups – Desmostylians – Kolponomos – bear-like, fed on marine invertebrates – Thalassocnus – an aquatic sloth!!! Challenges of the Marine Environment for Mammals • Can’t exchange gases continuously • Increased rate of heat loss • Resistance to movement (viscosity) • Differences in sound characteristics • Generally low light/visibility • but, provides support (buoyancy) • Level of adaptation depends on proportion of life spent in the water Some basic adaptations • Polar bears (least derived) – Mainly adapted for cold terrestrial environment – Too buoyant for any real diving but strong swimmers • Sea otters – Well adapted for life in the ocean – Spend much time rafting at surface but somewhat accomplished divers – Pinnipeds (seals, sea lions, walrus) – Amphibious but spend considerable time at sea – Limbs provide propulsion on land and sea – Dense fur and streamlined bodies – Carnivore-like dentition (differentiated teeth) – Sensory bristles (vibrissae) – Rely on vision/touch – Amazing diving capabilities • Sirenians (dugongs and manatees) – entire life at sea – Herbivores – Nostrils at dorsal tip of snout – Use vision/touch – Fat layer – Heavy bones – Modified tail for efficient propulsion – Cetaceans (whales, dolphins, porpoises) – Nostrils on dorsal surface of head (blowhole) – Great breath-holding capacity – Blubber and vascular heat-exchangers – Very streamlined – Horizontal flukes/efficient propulsion – Sound producing systems (echolocation in odontocetes)...
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This note was uploaded on 03/05/2011 for the course MMC 3061 taught by Professor Heithaus during the Spring '10 term at FIU.
- Spring '10
- The Land