Lecture 6. September 8, 2008 Finish Chondrichthyes 1. SHARKS & RAYS a. reproduction b. notable shark & ray orders c. shark conservation 2. Sarcopterygii vs. Actinopterygii 3. Story of the coelacanth a. Coelacanth biology b. Lungfish biology
mermaid’s purses
Lemon Shark Giving Birth
Whale Shark
whale shark video N39LJIhttp:// N39LJI
goblin shark
megamouth
megamouth video mnZv8Qhttp:// mnZv8Q start at 2:10
thresher shark (Alopiidae)
thresher shark video VRMFQhttp:// VRMFQ start at 5:30
basking sharks
great white shark
great white shark video OCqoohttp:// OCqoo
Order Carcharhiniformes (ground sharks) Family Carcharhinidae (requiem sharks) Largest Order - 8 families, 210 species Tiger shark Hammerhead shark
Order Carcharhiniformes (ground sharks) Family Carcharhinidae (requiem sharks) Bull shark Oceanic white tip shark Silky shark
Shark attacks on humans 35 to 55 unprovoked attacks each year 6 to 11 fatalities per year 54% of attacks on surfers/windsurfers 38% on swimmers/waders 6% on divers/snorkelers Regions with most shark attacks:
Shark attacks on humans 35 to 55 unprovoked attacks each year 6 to 11 fatalities per year 54% of attacks on surfers/windsurfers 38% on swimmers/waders 6% on divers/snorkelers Regions with most shark attacks: South Africa - 63 attacks from 1990 to 2003 Brazil - 57 “ “ “ “ Australia - 51
Shark attacks on humans 35 to 55 unprovoked attacks each year 6 to 11 fatalities per year 54% of attacks on surfers/windsurfers 38% on swimmers/waders 6% on divers/snorkelers Regions with most shark attacks: South Africa - 63 attacks from 1990 to 2003 Brazil - 57 “ “ “ “ Australia - 51 Florida - 311
dogfish sharks (Squalidae) dogfish shark
saw sharks pointed snout used to thrash and incapacitate small fishes
electric rays (Torpedinidae)
sawfish (Pristidae)
More sawfish pictures
Skates (Rajidae)
Myliobatiformes Sting rays (Dasyatidae)
Myliobatiformes Sting rays
Myliobatiformes Manta rays (Myliobatidae)
Weblinks: great white : megamouth: thresher: hammerhead: sawfish: manta ray: for ground and requiem sharks (family Carcharinidae), skates (family Rajidae), and sting rays (Dasyatidae) go to the following website and look up some details about one or two species. There is tons of really cool stuff on sharks at the Florida Museum of Natural History website. We could spend a lot of time on each of the various orders and families in the Elasmobranchii. Instead, I want you to look up something about each of the following groups. Find one or two facts that are of interest to you.
shark conservation soupfin sharks porbeagle direct targets of fisheries - two examples
shark conservation sharks as by-catch
Blue Shark - Common by-catch in swordfish fisheries blue shark swordfish
Discerning Characters of Sarcopterygii vs. Actinopterygii
Fleshy, lobed pectoral, pelvic, anal and second dorsal fin lobed, fleshy parts go up into fins
Class Sarcopterygii Three major living groups Coelacanthimorpha-coelacanths (two species) Dipnoi-lungfishes (six species) Tetrapoda (all non-fish vertebrates)
Order Coelacanthiformes Fossil record extends from M. Devonian (370 Ma) to Cretaceous (65Ma)
Order Coelacanthiformes Marjorie Courtenay-Latimer
Order Coelacanthiformes Smith describes the coelacanth, Latimeria chalumnae, discovered in 1939, a true living fossil
Bony plates Diphycercal tail Teeth 0n hard plates
Marjorie Courtenay-Latimer Brass plate at Latimer's Landing East London.
Order Coelacanthiformes “New” populaiton discovered at Sulawesi, Indonesia 1997
Order Coelacanthiformes “New” populaiton discovered at Sulawesi, Indonesia 1997 DNA analyses indicate divergence from L. chalumnae at Ma Described as a new species L. menadoensis
Order Coelacanthiformes