Marine Vertebrates

1
Marine Vertebrates

• Marine Biology
• Dr. Ouida Meier

2
Representative Marine Phyla

• Phylum Porifera
• Phylum Cnidaria
• Phylum Bryozoa
• Phylum Mollusca
• Phylum Annelida
• Phylum Arthropoda
• Phylum Echinodermata
• Phylum Chordata

3
Phylum Chordata

• Subphylum Urochordata
• Class Ascidiacea (tunicates)
• Class Thaliacea (salps, gelatinous thaliaceans)
• Subphylum Vertebrata this week.

All chordates possess at some time during
development a notochord (made of cartilage) along
midline of body, below a hollow dorsal nerve
cord, as well as a postanal tail and pharyngeal
pouches.
4
Subhylum Vertebrata

• Class Agnatha (jawless fish)
• Class Chondrichthyes (cartilaginous fish)
• Class Osteichthyes (bony fish)
• Class Reptilia (reptiles)
• Class Aves (birds)
• Class Mammalia (mammals)

5
Subphylum Vertebrata

• Class Agnatha (jawless fish)
• Class Chondrichthyes (cartilaginous fish)
• Class Osteichthyes (bony fish)
• Class Reptilia (reptiles)
• Class Aves (birds)
• Class Mammalia (mammals)

Whos missing?
6
Features of Vertebrates

• Postanal tail, pharyngeal pouches (chordate)
• Vertebral column (develops from notochord
  segmented)
• Specialized sensory organs
• Brain at anterior end of nerve cord
• Closed-loop circulatory system (heart, arteries,
  capillaries, veins)
• Myomeres (muscle segments)

7
Marine Fish

• Agnatha hagfish (most primitive), lampreys
• body fluids isotonic to seawater 30-50 in
  other vertebrates
• Chondrichthyes sharks, skates, rays
• large lt20cm to gt15m
• Osteichthyes bony fishes tarpon, eels salmon,
  sardines, lanternfish, toadfish, flying fish,
  seahorses, pipefishes, scorpionfishes, sculpins,
  basses, groupers, snappers, barracudas, wrasses,
  tunas, triggerfishes, molas, pufferfish, etc.
• bone stronger and lighter than cartilage small
  size, diverse adaptations and habitats

8
Body shape specialization

• High maneuverability (e.g., butterflyfish)
• Rapid acceleration (e.g., barracuda)
• Efficient cruising (e.g., tuna)
• Eating methods
• Ramming (e.g., sharks)
• Biting (e.g., triggerfish)
• Sucking (e.g., butterflyfish)

9
Marine Reptiles

• Snakes (61 species of true sea snakes, most of
  them highly venomous)
• Turtles (7 species of sea turtles)
• Iguanas (1 species of marine iguana, Galapagos
  Islands)
• Estuarine environments additional snakes,
  caymens, alligators, crocodiles)

10
Marine Birds

• Feathers and front appendages adapted for flight
• Species range of dependence on marine
  environment
• Ducks, geese, coots
• Shorebirds herons, stilts, sandpipers
• Albatrosses, petrels, gannets, pelicans, gulls,
  terns, murres
• Penguins
• Birds and Mammals are true homeotherms

11
Marine Mammals

• Order Carnivora
• Pinnipeds Seals, sea lions, walruses, sea otters
• Polar bears
• Order Cetacea
• Whales, dolphins, porpoises
• Order Sirenia
• Manatees, dugongs

12
Characteristics of mammals

• Viviparous
• Body hair
• Milk-secreting mammary glands
• Specialized teeth
• Separate reproductive / digestive tract openings
• other vertebrate groups oviparous or
  ovoviparous, and have a cloaca

13
Modern cetaceans

• Suborder Mysticeti baleen whales lack teeth
  have rows of baleen projecting from upper jaw to
  filter-feed
• Suborder Odontoceti toothed whales smaller
  specialized teeth help capture slippery fish,
  squid, other prey

14
Links

• Basic background on marine mammals
• Pinniped photo gallery
• Cetacean photo gallery
• National Marine Mammal Lab, Cetacean Assessment
  Program
• Sea Otter Evolution and Adaptations