Vertebrates descended from________ _________.
Bony Fish
What are the four levels of social structure of the resident Killer Whales?
matraline
pod
clan
community
What are the 5 defining characteristics of marine mammals?
Breath air
Give Birth to live young (not hatched from eggs)
Nurse their babies
Warm Blooded
Have fur or hair
What are the 5 problems mammals face with going deep in the ocean?
Pressure, Oxygen Consumption, Mammalian Bodies Float, Nitrogen Narcosis, and The Deep Ocean is Cold
How many millions of years ago did mammals evolve from reptiles?
300 mya
What are the three superclasses of marine vertebrates?
Agnatha, Pisces, and Tetrapoda
What is the life expectancy of resident killer whales at birth?
The average life expectancy is about 29 years for females and 17 years for males.
What are the four groups of marine mammals?
Cetaceans
Whales, Dolphins, and Porpoises
Pinnipeds
Seals, Sea Lions, and Walruses
Sirenians
Manatees and Dugongs
Fissipeds
Polar Bear and two species of Otter
How do humans avoid or deal with Nitrogen Narcosis?
Scuba divers follow strict diving charts with slow assents and descents.
Divers who experience nitrogen narcosis may have to spend time in specialized decompression chambers
Which animals are able and use echolocation?
Toothed Whales (odontocetes), Bats, and Humans (some blind people)
What is the basic body plan for all vertebrates?
Vertebral column or Notochord and a Spinal Chord
What are the three types of Killer Whales?
Transient, Resident, and Offshore
So how do marine mammals maintain their body temperatures?
Countercurrent heat exchange
Insulation (blubber, fur)
Behavioral strategies (coming to the surface to get warm)
High metabolism
Describe two ways marine mammals have evolved to reduce the effects of Pressure when diving deep?
-Over evolutionary time, most marine mammals have lost their external ears and sinuses.
Without air-filled ears, a diving marine mammal does not suffer the effects of changing pressure.
-Sea lions and Fur Seals do have ears.
During a dive their ears will fill with a bloody fluid, forcing any air out.
What are placoid scales?
Tiny teeth embedded in the skin (sharks)
What are the 3 classes of Tetrapoda?
Why is the life expectancy of male killer whales lower then female killer whales?
Males are larger and require more resources then females, increasing their vulnerability to starvation in years of low salmon abundance.
What is are the two main difference between seals and sea lions?
Seals lack ear flaps / Sea Lions have ear flaps
Seals can't rotate their flippers and don't move well out of water/ Sea Lions can rotate their flippers forward and are more mobile out of water.
What is the other name for the Mammalian Diving Reflex?
Bradycardia
What are two defining characteristics of reptiles?
Reptile skin is covered by scales to help prevent water loss.
Reptiles are Ectotherms (cold blooded)
What are the 6 evolutionary steps of Vertebrates from water to land?
In the following order: Notochord, Jaw, Four Fins, Limbs, Lungs, Dry Skin and Water Tight Eggs
Compare and contrast the three types of killer whales ( Give at least 2 differences of each type).
Resident- fish specialists, larger pods, small home ranges around large fish populations
Transient-mammal eating Killer Whales, small groups, large home ranges, pods are fluid and break up and join with others.
Offshore- thought to eat sharks, and live far from land, large range from Southern Ca to Bering Sea
Dolphins (Delphinidae) / Porpoises (Phocoenidae)
Teeth are cone-shaped / Teeth are flattened
Beak-shaped snout / Blunt snout
Hooked or curved dorsal fin / Small, triangular dorsal fin
Often seen at surface /Seen only briefly at surface
Give 4 adaptations that marine mammals have to help them store oxygen during a deep dive.
They store oxygen in their blood and their muscles rather than in their lungs.
Marine mammals have a very high blood to body volume ratio.
They have a higher percentage of red blood cells than most mammals (human 36%, seals 50%).
High concentration of hemoglobin in the blood and myoglobin in their muscles.
What are the defining characteristics of Sea Birds?
Ability of feathers to resist water
Presence of Salt Glands
Curved Bills
Webbed Feet