Where did we really come from? Miss Augulewicz Vertebrate Evolution Where did we really come from? Miss Augulewicz

Vertebrate Innovations Vertebral Column Series of separate bones firmly joined as a backbone that defines the major body axis

Vertebrate Innovations Cranium Supports and protects the sensory organs (eyes, ears, nose, mouth) and your brain

Step 1: Pre-vertebrates Lancelet performed suspension feeding using cilia and mucus

Mouth gets bigger Muscular pump forms that can open and close Water & food are taken in and pumped out Reinforced by cartilage

Step 2: Agnathans-Jawless fish evolve Feed using their muscular pharynx, not cilia and mucus Lampreys, hagfish

Step 3: Gnathostomes- Jawed fish The jaw evolves! Mouth opens, pressure sucks large food in, jaw closes No longer need pharyngeal slits to eat

Our ancestors were jawed fish: gnathostomes Chondrichthyes (Sharks and stingrays) evolved in one direction they had bone then lost it and are mostly cartilage Osteichthyes (bony fish) evolved in another direction Kept the bone Ancestors to all present day bony fish & vertebrates= SUCCESSFUL!

Half a billion years summed up in a few minutes… http://www.youtube.com/watch?v=kgZRZmEc9j4

Your Inner Fish SO….Looking back MUCH further than the chimpanzees, humans haves some other pretty old and interesting ancestors.... FISH!

How did we get on land? Meet the lungfish

Lungfish Lived in shallow fresh water that would sometimes dry up Breathe using primitive lungs if no water Breathe using gills if in water

Eventually fish evolved to come out of water…..

We look at the fossil record. How did we learn this? We look at the fossil record.

Tiktaalik Tiktaalik lost some fish characteristics and gained lungs, arms & legs, primitive ears

Finding tiktaalik! http://www.youtube.com/watch?v=yvDQCa7rleI

What evolved next? So they made it to land...but they aren’t fish anymore, what are they??

Amphibians Evolution of lungs from the gut Strengthening of limbs Need to stay near water to lay eggs

Reptiles Can reproduce on land by laying eggs Get stronger limbs, use muscle and less energy to move

A new egg! Amniotic egg Doesn’t need to be laid in water Our ancestors can move to dry land! Leathery shell chorion membrane allows for gas exchange, yolk sac provides food, allantois collects waste, amnion fluid surronding embryo

From 2 different groups of reptiles we got.... Birds! Mammals!

First mammals.. Evolved from a reptile- mammal ancestor group called Therapsids. Sort of look like rodents! Or weird dogs! Inostrancevia Oligokyphus

Mammalian characteristics Mammary glands: To feed milk to our young Fur or hair Endothermic: maintains temperature from metabolic heat The world got cold but mammals could stay warm and survived and radiated Live in water or land

There are three types of mammals based on their mode of reproduction Monotremes lay eggs. Marsupials have young that develop in the uterus for a short term. At birth, marsupial young crawl through mother's fur and into a pouch on the female's body to feed on mother's milk. Placental mammals like humans develop through advanced stages in the uterus and receive maternal nutrients across the placenta.

Life of Mammals http://www.youtube.com/watch?v=2lCKc8tURtc&list=PL D941E65FBD70DB46

Birds (Aves) Birds came from the dinosaurs! This fossil, Archaeopteryx was once a dino with feathers!! I can’t really talk too much about birds because they are my favorite and it would become a bird class.

Remember all the came before us!