Whales powerpoint


Published on

Published in: Travel, Technology
  • Be the first to comment

No Downloads
Total views
On SlideShare
From Embeds
Number of Embeds
Embeds 0
No embeds

No notes for slide

Whales powerpoint

  1. 1. Whales
  2. 2. • Evolved from land mammals 50 to 65 million years ago• Evolved from ungulates (related to horse and sheep)
  3. 3. Temperature Regulation• Blubber (also for buoyancy and energy storage)• Counter-current blood flow –warms blood as it returns tocore of body• Muscles generate heat• Low surface area to volumeratio - little surface in contactwith water to lose heat
  4. 4. Oxygen• blowhole (nostrils) on head – easier• Empty and fill lungs quickly (2 seconds for a fin whale)• Large lungs• High gas exchange rate (absorb 90% of oxygen - humans absorb 20%)
  5. 5. Oxygen• Many red blood cells, hemoglobin – carries oxygen• myoglobin - carries additional oxygen• Shunt blood from non-vital organs (stomach, kidney) when diving to vital organs (brain, heart, muscles)• Slow heartbeat rate when diving
  6. 6. Propulsion Through the Water• Streamlined• Internalized body parts - ear, penis, mammary glands – reduces friction• Shorter appendages – forelimbs for steering• Loss of hind limbs• Loss of hair
  7. 7. Propulsion Through the Water• fluke (tail) for propulsion – Up and down (unlike fish = side to side) – ↑ surface area – Also to identify individuals - like fingerprint• flippers – for steering and balance
  8. 8. Sensing the Environment• Good eyesight – but little to no light• echolocation - biological SONAR – find and maybe to stun prey• Very good hearing - sound travels faster in water than in air• ex: humpback songs for communication – social, territorial
  9. 9. Pressure• Collapsible lungs• Nostrils close to prevent water from entering• Do not get the bends – when we dive if ascend too quickly, dissolved nitrogen forms bubbles – pain, embolism, death• Tissues and blubber have higher affinity for nitrogen
  10. 10. Types of Whales• Toothed whales – suborder Odontoceti• Baleen whales – suborder Mysticeti
  11. 11. Types of Whales – Toothed Whales• Have teeth – to catch prey, not chew• Eat mostly fish and squid - killer whales eat seals• Dive deeper• Most do not migrate• Ex: sperm, pilot, killer whales, dolphins, porpoises• Ex: sperm whales dive > 3,500 feet for giant squid, up to 75 minutes
  12. 12. Types of Whales – Baleen Whales• No teeth - 600 - 800 baleen plates to filter krill and other items• ex: blue whale eats 4 tons of krill per day• Not deep divers• ex: humpback - lung feeding (lunge forward, pleats open), flick feeding (flick tail), bubble feeding (blow bubble net and swim up)
  13. 13. Types of Whales – Baleen Whales• pleats – folds under mouth – open like accordion when feeding
  14. 14. Types of Whales – Baleen Whales• ex: humpback - lunge feeding (lunge forward, pleats open), flick feeding (flick tail), bubble feeding (blow bubble net and swim up)
  15. 15. Types of Whales – Baleen Whales• ex: blue, humpback, right, gray, fin• North to feed, south to breed - behavioral adaptation – north - summer for krill – south - winter to raise young• ex: gray whales, 3 monthmigration, Arctic to Baja, CA,6,000 mi one way
  16. 16. Reproduction• coincides with migrations• internal fertilization• live young born• nurse and grow quickly, ex: blue whale, 130 galmilk/day, grows 200 lbs./day• low birth rate• pods – family groups of whales - social
  17. 17. Whale Behavior• Breaching – jumping out of water – to remove parasites, social behavior, stun prey?• Spyhopping – sticking head out of water – curiosity, look for prey, communication?
  18. 18. Whale Behavior• Beaching – swimming up onto beach• Can be one or many individuals• Cannot hold up body on land• Reasons – noise pollution, disease, injured, red tide, anomalies in magnetic field, lost?
  19. 19. Whaling• Hunted by indigenous people• Problems starting in 1600s –industrial whaling – not for food – blubber – oil for lamps and soap – baleen – anything we use plastic for today – combs, umbrellas
  20. 20. Whaling• Low reproductive rates – one young every 2 to 3 years• Could not withstand whaling pressure• Better technology made things worse - factory ships, harpoons
  21. 21. Whaling• International Whaling Commission (IWC) group of countries to regulate whaling industry• Marine Mammal Protection Act – 1972 – U.S. law – bans hunting and harassment of all marine mammals