Sharks
Upcoming SlideShare
Loading in...5
×

Like this? Share it with your network

Share
  • Full Name Full Name Comment goes here.
    Are you sure you want to
    Your message goes here
    Be the first to comment
No Downloads

Views

Total Views
1,992
On Slideshare
1,973
From Embeds
19
Number of Embeds
2

Actions

Shares
Downloads
56
Comments
0
Likes
2

Embeds 19

http://lifeplaisir.blogspot.com 17
http://lifeplaisir.blogspot.ae 2

Report content

Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
    No notes for slide

Transcript

  • 1. Sharks Read pages 155-159 & 174-177 See also: http://www.flmnh.ufl.edu/fish/education/questions/basics.html
  • 2. Types of Fishes – Where Do Sharks Fit In?
    • Three types: Jawless, Cartilaginous, & Bony
    • Sharks fall into the Cartilaginous category
      • Primitive fishes
      • No true bones, only cartilage
      • Related to skates and rays
      • Most are harmless
      • See the model in C114
  • 3. Shark Diversity
    • The smallest shark is a deepwater dogfish (adults are about 8 inches long) 
    • The largest shark is the whale shark
    • (a planktivore) 
    • The fastest shark is the shortfin mako (swims up to 20 mph)
    • (Note: Average person swims about 3 mph)
    http://dsc.discovery.com/videos/ultimate-guide-to-sharks-the-many-species-of-sharks.html
  • 4. Shark Bodies
    • Notice that sharks are fish and obtain oxygen from the water through their gills-usually 5 – 7 gills
  • 5. Shark Bodies Cont.
    • Lost teeth are replaced in a “conveyor belt” system, with back teeth moving forward to replace lost ones
  • 6. Shark Bodies Cont.
    • Placoid Scales – sharp-edged scales can injure prey; gives shark skin a sandpaper-like feel
    • Liver – very fatty; helps shark maintain buoyancy
    • Tail-upper lobe is usually longer for better power & thrust
    • Usually two dorsal fins, paired pectoral fins
  • 7. Shark Reproduction
    • Fertilization is internal
    • Males use claspers to insert sperm into female’s cloaca
  • 8. Shark Reproduction Cont.
    • Some sharks are Oviparous (lay an egg-mermaids’ purse)
    • Some sharks are Ovoviviparous (have an egg that develops inside female-sometimes eating siblings!)
    • Rarely, sharks can be Viviparous (Live-bearers-like mammals)
    http://dsc.discovery.com/videos/ultimate-guide-to-sharks-how-are-sharks-born-take-a-look.html
  • 9. Shark Camouflage
    • Countershading – darker on dorsal surface to blend with the deeper water or the sea bottom & lighter on ventral surface to blend with lighter colored surface waters, making it difficult for both predators & prey to see a shark
  • 10. Shark Trouble
    • Most sharks need to force water over gills to breathe, and can “drown” when trapped in nets
    • Skin, oil, and fins are overharvested to the point of near extinction for some species
    • PSA aimed at stopping these practices: http:// www.youtube.com/watch?v =fkxoRPv4ugE&playnext=1&list=PLB4E6B7A755C66293
  • 11. Additional Shark Links
    • More on the importance of sharks in healthy oceans: http://www.youtube.com/watch?v=xVKrwsXvC0A&feature=autoplay&list=PLB4E6B7A755C66293&index=5&playnext=2
    • Clearinghouse of all known Shark links: http://www.postmodern.com/~fi/sharklinks/links.htm
    • More general shark information: http:// www.youtube.com/watch?v =xVKrwsXvC0A&feature= autoplay&list =PLB4E6B7A755C66293&index=5&playnext=2