Unit 2 Exam Review!

Unit 2 Exam Review!

Birds and Dinos: Related? YES!

• If two species share traits, they are probably related!

• The more traits in common, the more related two species are.

• This also means two species evolved from a common ancestor - like a great, great grandparent.

Multiple Choice

How do we know birds and dinos are related?

• they lived at the same time

• they lived in a similar area

• they live in similar climates

• they have traits in common

Multiple Choice

The flying dinosaur Archeopatryx is in the middle of the picture. What traits does it have in common with today's birds? (TWO answers)

• they both have a 2-fingered hand

• they both have a wishbone

• they both have shafted feathers

• they both have a toothless beak

Mr. Adler's Favorite Fossil!

• This Archeopatryx fossil shows that some dinosaurs had feathers!

• Dinos and birds both have a hole in their hipbone, a wishbone, and protected nests full of eggs.

• All of those traits tell us dinos and birds ARE related, and evolved from a common ancestor!

Cladogram:

Tree of Life

• When we know enough about different traits, we can make a model like this!

• It shows us how evolution has happened over time, and how species are related.

• Let's practice reading one ...

Multiple Select

What is TRUE about this tree of life? Pick MORE THAN ONE.

• All of these species are at least a little related.

• Crocodiles are most related to amphibians.

• Primates are most related to rodents.

• The common ancestor of crocodiles and birds laid eggs with shells.

The Tree of Life

• The only wrong answer was about crocodiles being most related to amphibians.

• Crocs and BIRDS are on the same branch, evolved from a common ancestor that laid eggs with shells!

• All of these animals are at least a little related, since they all evolved from a vertebrate with a backbone.

Oh no! No tree!

• We don't need a tree of life to know who is related.

• If we see the traits, we can figure out for ourselves who shares the most traits.

• Those species are most related, and evolved from a common ancestor!

Multiple Select

Which TWO species here are the most related?

• banana

• lemon

• onion

• seaweed

But not ALL traits ...

• Some traits are better than others at telling you what species are related.

• See these wings? Big deal.

• Similar OUTSIDE parts could just be adaptations to deal with the same kind of environment.

• They don't mean the species are related.

Multiple Choice

Are birds and butterflies related?

• YES!

• NO!

• We need more evidence ...

Anatomy:

Parts InSiDe

• To know if species are related, the BEST traits to use are the anatomical structures.

• Remember, anatomy means the parts InSiDe.

• So we have to look CLOSER, inside, to see who's related!

Multiple Choice

What are the best traits to use to know if species are related?

• analogous structures

• anatomical structures

• scientific structures

• vestigial structures

Multiple Choice

Look at the picture of the bat, bird, and bee. Are they related? Did they evolve from a common ancestor?

• YES! They all have wings.

• Sort of. They're related, but they didn't evolve from a common ancestor.

• NO. The inside parts are totally different!

Multiple Select

This is a picture of the inside of a human hand an a frog's arm. What can we infer from this evidence? Pick TWO.

• Humans and frogs both climb in trees.

• Humans are going to evolve into frogs in the future.

• Humans and frogs are probably related.

• Humans and frogs evolved from a common ancestor.

Similar parts inside (aka anatomy) ...

• And we can conclude the species ARE related!

• And evolved from a common ancestor!

• (Weird, but true. You and frogs are basically distant cousins.)

Evolution!

• Evolution is the slow change of a species over time

• Traits that make you more likely to survive are passed down, and with each generation of kids, the species changes a little!

Multiple Select

Based on this evidence, how did humans evolve over time? Pick TWO.

• We can observe the skulls get larger over time.

• We can observe the bodies get more upright.

• Maybe humans developed larger brains and more intelligence.

• Maybe humans started standing up more.

Vestigial Structures

• Sometimes, even if we don't see all the fossils in between, we can make a good inference.

• We can use a vestigial structure - a useless part of a species!

• These parts are useless to an animal NOW, but tell us about the species' ancestors!

Multiple Select

Which of these is a vestigial structure? Pick TWO.

• whale skull

• whale pelvis

• human pelvis

• human tailbone

Vestigial Structures

• A human pelvis is NOT vestigial - we need that to walk!

• A whale pelvis IS vestigial - there's nothing attached, it doesn't need it.

• Remember, vestigial structures are USELESS parts!

Multiple Select

Based on the whale's vestigial pelvis, what can we conclude about whale ancestors? Pick two.

• they swam in the ocean

• they walked on land

• they had back legs

• they ate small fish

Whale Ancestors!

• This is what scientists think ancient whales looked like!

• They have made that inference all because of the whale's pointless pelvis - the vestigial hip bone!

But what about humans?

• We have a tailbone, but no tail.

• We have an appendix, but don't eat leaves.

• We have muscles for swinging through trees, but they don't work.

• We have goosebumps, but they do nothing.

• So what?

Multiple Select

Based on the human's vestigial structures, what might humans have been like in the past? Pick more than one.

• We swung through trees like monkeys.

• We ate plants and other tough foods.

• We had a tail.

• We had fur.

Let's Review :)

• More traits in common two species have, the more related they are.

• When we look at a tree of life diagram, we can see related species, but some are more related than others.

• The best traits to use are anatomical ones, parts inside.

• Same parts inside, like bones? Species are probably related, and evolved from a common ancestor.

• When we observe vestigial structures - useless parts - we can see what a species' ancestors might have been like!

Open Ended

What have you learned from this review?

What To Do NEXT

• Remember, tomorrow is the test.

• You can play this Quizziz again.

• You can study vocabulary in Quizlet.

• You can play the Kahoot again.

• When you think you're ready ... stop studying :)