Fish, reptiles, birds and mammals Flashcards
What is a fish?
vertebrate
almost all species aquatic
Distinguishing features:
- fins
- scales
- gills
What is the importance of fish?
Evolutionary- first lineage of vertebrates
Most diverse extant vertebrates (35,000 spp)
Food- cheap and widely available
Commerical- fisheries and aquaculture
Other products health, industry
Recreation and tourism
What is the external anatomy of fish?
Scales
Lateral line
Fins- median and paired
Gills- Elasmobranchs: 5-7 pairs, individual slits
- Bony fishes (teleosts): 4 pairs, operculum (gill cover)
What are the gill structures?
Elasmobranch
Osteichthyes
What is the pseudobranch?
Is a gill like structure found in most fish species that is attached to the inside of the operculum
Rich in carbomic anhydrase- acidifies blood and releases oxygen in blood to eye
What is rete mirabile?
In fish, the rete mirabile is a critical adaptation used to supply oxygen to tissues like the eye and the swim bladder, where high oxygen concentrations are essential
Counter-current exchange
In eye, this maintains high blood acid in vessels supplying eye (carbonic acid)
Enhances oxygen unloading to supply eye by direct diffusion
What sub phylum exist within the phylum Chordata?
Sub-phylum Urochordata
Sub-phylum Cephalochordata
Sub-phylum Vertebrata
What are the ancient lineage representatives?
Class Sarcopterygii:
- Coelacant- sub class Coelocanthamorpha
- Lungfishes- sub class (infra-class) Dipnoi
Class Actinopterygii
Bichirs- sub class Cladistia
Gars- sub class Neopterygii, order Semionotiformes
Bowfin- sub-class Neopterygii, order Amiiformes
What are the chondrichthyes?
the cartilaginous fishes
What classes exist in the superclass Ganthostomata?
Super class Ganthostomata: jawed fishes
Class Chondrichthyes: cartilaginous fishes
Sub class Holocephali: chimaeras
Sub class Elasmobranchii (plate gills): sharks, skates, rays
How are the sub class Holocephali described?
Single gill flap covering 4 internal gill openings
Male intromittent organs (claspers)
Males have frontal (tentaculum) on forehead in some species
Reproduce via shelled eggs
First dorsal fin erectable (with poison spine)
Oily liver
What super order exists in the sub class Elasmobranchii?
Super order (cohort) Euselachii
8 orders of sharks
1 (or 5) orders of rays
What are the characteristics of the sharks and allies?
5-7 external gill slits
Spiracular opening
Dorsal fins not collapsible
Male intromittent organs (claspers)
Placoid, mushroom-shaped scales
Oily liver
No gas bladder
Varied reproduction (eggs, ovoviviparity, viviparty)
What are the other characteristics of the sharks and rays?
5 gill slits
Flattened teeth
Spiracles
All lay eggs
Dorsal fins reduced/absent
What are the Osteichthyes?
The bony fishes
What sub-classes exist in the class Actinopterygii?
Sub-class Chondrostei
Order Acipenseriformes- sturgeons, paddlefishes
Sub-class Neopterygii
Order Semionotiformes- Gars
Order Amiiformes- Bowfin
Division Teleostei- modern bony fishes
38 orders extant
Why are protrusible jaws important in fish?
Enabled by ligamentous connections between free floating bones in the jaw (premaxilla, maxilla, and mandible)
Allows formation of pipette mouth
Suction feeding
Pulls items into jaws
Increases attack sped (up to 40%)
What orders exist in the Teleosteans?
Clupeiformes
Gadiformes
Cypriniformes
Anguilliformes
Salmoniformes
Pleuronectiformes
Largest: Perciformes
How are the super order Acanthopterygii?
Spiny rayed fishes
10,000 species (mostly Perciformes)
Most abundant group within the vertebrates
Why are paired fin positions important in fish?
Anterior positioning of pelvic fins
Increased maneuverability
Fine control
Use of complex habitats e.g. coral reefs for feeding and defence
Also requires development of gas bladder
Neutral buoyancy
What are the marine reptiles?
Lizards- 1 species
Crocodilians- 1 species
Turtles- 7 or 8 species
Snakes- 60 species
What are the lizards?
Galapagos marine iguana
What is an example of the crocodilians?
Australian Marine crocodile
What are the different Marine turtles
Green (+black)
Leatherback
Loggerhead
Ridley’s
Hawksbill
Flat back
What family do the sea snakes belong to?
Family Hydrophiidae
Sub Laticaudinae
17 genera
62 species
What class do the birds belong to?
Class Aves
What are the marine orders of the birds?
Sphenisciformes (penguins)
Procellariiformes
Pelecaniformes
Charadriiformes
What are the different types of penguin?
Gentoo
Chinstrap
King
Rockhopper
Emperor
What are the characteristics of penguins?
Flightless
Sub-cutaneous fat layer (warmth)
Divers
Feather adaptation for enhanced exit from water
What are the types of procellariiformes?
Albatrosses
Shearwaters fulmars
Diving pelicans
What are the types of pelecaniformes?
Tropic birds
Pelicans
Gannets
What are the types of Charadriiformes?
Skuas
Gulls
Terns
Skimmers
Auks
Why is Scotland significant for N Atlantic birds?
As a breeding area for such birds
What orders exist within the sea mammals?
Order Cetacea
Order Sirenia
Order Carnivora
Sub order Pinnipedia
What does the order Cetacea consists of?
Baleen whales- 15 spp
Toothed whales- 72 spp
How do baleen whales feed?
Filter feeders
What are the order sirenia?
Manatees, dugongs, 7 species
Manatees- Teeth continually replaced. Coastal water and freshwater distribution
Dugongs- Tusk like incisors, only marine mammal to be truly herbivorous
