¿ what anatomical/physiological features distinguish vertebrates?

The vertebrate story…

The vertebrate story…

The vertebrate story…

The vertebrate story…

AgnathaExtinct: Ostracoderms

*Coverd by bony armor

*Mostly small fish 2cm (some up to 2m)

*Small mouth openings

*4 openings on dorsal surface of head

*Extinct after abundance of jawed fishes on the scene

http://universe-review.ca/I10-27-jawlessfish.jpg

AgnathaExtant: “Cyclostomes”Hagfish and Lamprey

*Are not as closely related as might appear

*Hagfish are scavengers that lack the rasping denticles of lamprey

*Most Lamprey are parasitic

http://www.exploretheabyss.com/photo/gallery/gallery/ds_trawl/images/HagfishLR.jpg

http://www.nwrc.usgs.gov/world/images/lamprey.jpg

http://www.glaucus.org.uk/sea-lamprey-sucker-RL.jpg

Extant Jawless fishes…

http://tolweb.org/Vertebrata

Extant Jawless fishes…

http://www.bio.uio.no/akv/english/research/mzk/benthos_pictures.html

http://www.youtube.com/watch?v=g8pONkTyk2c http://www.youtube.com/watch?v=NYRr_MrjebA&NR=1

Extant Jawless fishes…

http://bakkouz.net/pix/Hagfish.jpg

http://sophont.blogspot.com/2004_02_01_archive.html

Extant Jawless fishes…

http://www.uoregon.edu/~joet/Pictures-Pages/Image5.html

http://a.abcnews.com/Technology/AmazingAnimals/popup?id=4958186&contentIndex=1&page=6&start=false

http://www.gma.org/fogm/myxine_glutinosa.htm

Extant Jawless fishes…

Broad-gilled Hagfishhttp://www.austmus.gov.au/fishes/fishfacts/fish/ecirrhatus5.htm

http://www.austmus.gov.au/fishes/fishfacts/fish/ecirrhatus6.htm

Broad-gilled Hagfish

Extant Jawless fishes…

Extant Jawless fishes…

Extant Jawless fishes…

Extant Jawless fishes…

http://www.daylife.com/photo/0g1T92TaxK623

http://www.daylife.com/photo/0e9DdRDaeV8qa

Extant Jawless fishes…

http://www.gma.org/fogm/Petromyzon_marinus.htm

Extant Jawless fishes…

Extant Jawless fishes…

http://www.gma.org/fogm/Petromyzon_marinus.htm

http://en.wikipedia.org/wiki/File:Boca_de_lamprea.1_-_Aquarium_Finisterrae.JPG

http://www.biology.duke.edu/bio217/2005/ncy/sea%20lamprey.html

Extant Jawless fishes…

http://www.rsc.org/chemistryworld/News/2005/September/03100501.asp

Extant Jawless fishes…

http://oregonstate.edu/dept/ODFW/NativeFish/Lamprey.htm

Extant Jawless fishes…

Extant Jawless fishes…

Extant Jawless fishes…

Extant Jawless fishes…

Extant Jawless fishes…

Gnathostomes3 groups appeared in the Paleozoic:

1) Placoderms (ex. Arthrodires) had large boney plates and paired fins

http://www.noaca.org/earlgeo.gif

http://www.cnrs.fr/cw/dossiers/dosevol/imgArt/dioram/PaleozoDevon/Zimg/dicksonosteus.jpg

Gnathostomes3 groups appeared in the Paleozoic:

2) Chondrichthyans (cartilagenous fishes)*Includes sharks, rays, skates, and ratfish

*Cartilaginous skeletons

*Many with placoids

*No bony operculum

http://www.lifeglobe.com/images/product/Sharks/sharks04_r2_c2.jpg

http://www.pangaeadesigns.com/_graphics/page/fish/large/ratfish.jpg

Gnathostomes3 groups appeared in the Paleozoic:

3) Teleostomes (spiny and bony fishes)

*Acanthodians are (spiny fishes) are extinct

*Had skeleton of bone and cartilage

*Had an operculum

http://sps.k12.ar.us/massengale/images/R-acanthodians.gif

OsteichthyansShared ancestors with tetrapods

Have an air sac

Dermal bone

Paired fins… either ray finned (actinopterygii) or fleshy finned (sarcopterygii)

http://www.paleodirect.org/fg009.htm

ActinopterygiiBasal groups include Sturgeon and Paddlefish

http://www.hellscanyonsportfishing.com/images/sturgeon%20pictures/Kevin%20&%20Sturgeon%202.jpg

http://www.digimorph.org/specimens/Polypterus_senegalus/whole/specimen.jpg

ActinopterygiiAdvanced groups include Gars, Bowfins and Teleosts (most other bony fish)

http://www.sdafs.org/laafs/Amazing%20Fish%20Pictures/Big%20Alligator%20Gar%2009-03.JPG

SarcopterygiiHave fleshy lobed fins, internal nares and a bony operculum

2 major clades:

Actinistians, extinct except “coelocanths”

Rhipidistians (and dipnoi)“lungfish”

http://kentsimmons.uwinnipeg.ca/16cm05/1116/34-14-Coelocanth.jpg

http://www.bertsgeschiedenissite.nl/geschiedenis%20aarde/lungfish.jpg

Amphibia*Paraphyletic group… omitting amniote descendants

*Extinct groups include Labrynthodonts (Ichthyostega)

*Extant group (Lissamphibia) includes:

Apoda (caecilians)

Urodela (salamanders)

Anura (frogs)

http://news.siu.edu/news/May05/images/salamander.jpg

http://www.yesnet.yk.ca/schools/wes/webquests_themes/frogs_theme/frogs_K/frog_species/barred/images/

barred_leaf_frog_jpg.jpg

http://www.bbc.co.uk/radio4/science/media/Btaitanus-PC1b.jpg

AmniotesGroup includes Reptiles and Synapsids

Reptilia (paraphyletic)

Chelonia (testudinea) “turtles”

Rhynchocephalians “tuatara”

Squamates “lizards, snakes etc.”

Crocodylians “crocodiles” etc.

Aves “birds”

SynapsidsAmniotes with synapsid skull, hair, mammary glands & nipples (most)

Mammalia

Monotremata

Mammalia

Marsupialia

Mammalia

Insectivora

Mammalia

Xenarthra

Mammalia

Tubulidentata

Mammalia

Pholidota

Mammalia

Chiroptera

Mammalia

Primates

Mammalia

Lagomorpha

Mammalia

Rodentia

Mammalia

Carnivora

Mammalia

Pinnipedia

Mammalia

Perissodactyla

Mammalia

Atriodactyla

Mammalia

Hyracoidea

Mammalia

Proboscidea

Mammalia

Sirenia

Mammalia

Cetacea