Terminology

Chondrich... Abbreviation
Cartilage

Overview

All Deuterostomes
Echinoderms
Hemichordates
Cephalochordates
Urochordates
Vertebrates

Aquatic Vertebrates

Echinoderms
Bilateral symmetry as larvae.
Radial symmetry as adults.

Star fish, sea urchins, sea cucumber.

Urochordates

Sea squirts, tunicates

No coelom, open circulation, asexual or bisexual
Chordate hallmarks only in embryos

Fishes

Outgroup
Hagfish
No vertebrates
Jawless Fishes
Hagfish & Lampreys (parasitic)
Chondrichthyans
First fish with jaws
Cartilage fish, not bony
Ray-Finned Fish
First boney fishes
Vertebral column, skull, brain, heart
Lobe-Finned Fishes
Lobe-fins precursors to tetra-pod limbs
Coelacanth, joints start transitioning to bone.
Tetrapod limbs are modified fins.

Tilaalik Roseae

Land Vertebrates

Amniotic Eggs
Allows reptiles/mammals to move further onto land.
Amniotic egg becomes further modified in mammals.

Reptiles & Birds

Amphibians
Have gas exchange through their skin.
Have moist, slimy skin.
Require water for reproduction.
Reptiles
Do not have slimy skin.
Do not exchange gas through their skin.
Their skin is made from keratin.
Have amniotic eggs.
  • Lay eggs outside their body
  • Eggs maintain an aqueous environment (porous).
Mammals
Have amniotic eggs.
  • Feed their young through mammary glands.
  • Placental: circulatory system bridges fetus to mother.
  • Fetal hemoglobin has higher affinity for oxygen from mother's blood.
Birds
Feathered reptiles.
Flight has evolved 3 separate times in vertebrates.
  • Analogous function; Homologous bone evolution.

Primate Phylogeny

Wet-Nosed Primates
Lemurs
Dry-Nosed Primates
Orangutans
Gorilla
Apes
Humans

Humans diverge from the LUCA of chimpanzees and bonobos.

Mammals

Mammals
Out-group are reptiles
Have mammary glands

Types of Mammals

Marsupials
Placental mammals.
Live births, nurtured in a pouch.
Eutherians
Placental mammals.
Live, autonomous births.

Study Guide