Figure 24-9-Table 24-1

Figure 24-4a

Living species “succeed” fossil species

Fossil sloth from SouthAmerica

Present-day sloth fromSouth America

Figure 24-4bTransitional forms during the evolution of whales

Pakicetus, about 50 myo

Ambulocetus, about 49 myo

Rhodocetus, about 47 myo

Basilosaurus, about 38 myo

Figure 24-5a

The human tailbone is a vestigial trait.

Humancoccyx

Capuchinmonkey tail

(used for balance, locomotion)

Figure 24-6

Four mockingbird species on the Galápagos islands

Westernislands

Nesomimus parvulus

Darwin reasoned that they share a common ancestor.

Southernislands

Centralislands

Easternislands

Galápagosislands

Nesomimus melanotis

Nesomimus macdonaldiNesomimus trifasciatus

Mockingbirds from….

Southernislands

Easternislands

Westernislands

Centralislands

An ancestral populationcolonized the islands

Over time, thepopulationdiversified into several distinct species on different island groups

Figure 27-2Homoplasy: Traits are similar but were not inherited from a common ancestor.

Homology: Similarities are inherited from a common ancestor.

Ichthyosaur

Synap

sids

Monotre

mes

Mar

supia

lsEle

phants

Primat

es

Rodents

Whal

es a

nd

dolp

hins

Ptero

saurs

Dinosa

urs

Birds

Ichth

yosa

urs

Lizar

ds

Common dolphin

Flatw

orms

The dolphin and ichthyosaurlineages are far apart on theevolutionary tree, suggestingthat they are not closelyrelated

The members of lineagesbetween the dolphins andichthyosaurs do not haveadaptations such as:– streamlined bodies– long jaws filled with teeth– fins and flippers

Fruit-fly Hox complex

Human Hox complex

The genes in the Hoxcomplexes of fruit fliesand humans have similarsequences and are in thesame order on theirchromosomes

Infer that commonancestor had 8Hox genes

Annelids, mollusks, andechinoderms also haveHox genes

(inse

cts,

spid

ers,

Arthro

podscr

ustac

eans)

leec

hes)

(ear

thw

orms,

Annelid

s

squid

)

(snai

ls, c

lam

s,

Mollu

sks

Echin

oderm

s

(sea

sta

rs,

sand d

ollars

)

Chordat

es

(ver

tebra

tes)

Figure 24-7

Aniridia (Human)

eyeless (Fruit fly)

Only six of the 60 amino acids in these sequences are different. The two sequences are 90% identical.

Amino acid sequence (single-letter abbreviations):Gene:

Figure 24-8

Chick Human House cat

TailTailTail

Gill pouch Gill pouch Gill pouch

Figure 24-9

Turtle Human

Humerus

Radius and ulna

Carpals

Metacarpals

Phalanges

Horse Bird Bat Seal

Figure 24-13b-setup

Figure 24-13c-results

Figure 24-14

Overall body size has decreased

No net change in beak size over this interval

Beaks have become more pointed

Figure 27-8a

The Precambrian (Hadean, Archaean, and Proterozoic Eons) included the origin of life, photosynthesis, and the oxygenatmosphere.

Format

ion o

f sola

r sys

tem

Moon fo

rms

Earth

form

atio

n com

plete

Liquid

wat

er o

n Ear

th

First o

cean

s; h

eavy

bom

bardm

ent

fr

om s

pace

ends

Orig

in o

f life

First e

viden

ce o

f photo

synth

etic

c

ells

First e

viden

ce o

f oxy

genic

p

hotosy

nthes

isFirs

t rock

s co

ntain

ing o

xygen

(i

n atm

ospher

e an

d oce

an)

First e

ukary

otic fo

ssils

First p

hotosy

nthet

ic e

ukary

otes

First r

ed a

lgae

; firs

t evi

dence

o

f sex

ual s

truct

ures

First l

ichen

-like

org

anis

m

First s

ponges; f

irst b

ilate

rally

s

ymm

etric

anim

als;

oce

an

com

plete

ly o

xygen

ated

Proterozoic Eon

Multicellularorganisms beginto diversify slowly

Most of Earth is coveredin ocean and ice.

All life is unicellular

Position of the continents unknown

Archaean EonHadean Eon

Millions of years ago (mya)

Figure 27-8b

Phanerozoic Eon: The Paleozoic Era included the origin early diversification of animals, land plants, and fungi.

First c

omb je

llies

, arth

ropods,

v

erte

brate

s, o

ther

phyl

a

Cambrian

Algae abundant,marineinvertebratesdiversify

Arthro

pods div

ersi

fy;

fi

rst e

chin

oderm

First b

ryozo

ans

(new

est

a

nimal

phyl

um)

First l

and p

lants

First m

ycorr

hizal

fungi (

Glo

mal

es)

First c

artil

agin

ous fis

h

First b

ony fis

h

First i

nsect

s

First f

ish w

ith ja

ws

First f

erns,

vas

cula

r pla

nts,

a

scom

ycet

e fu

ngi, lic

hens

on land

First t

ree-

size

d pla

nts

First w

inged

inse

cts

First t

etra

pods (a

mphib

ians)

First s

eed p

lants

First p

lants

with

leav

es

First r

eptil

es

First m

amm

al-li

ke re

ptiles

First b

asid

iom

ycet

e fu

ngi

First v

esse

ls

in

pla

nts

Ordovician Silurian DevonianCarboniferous

PermianMississippian Pennsylvanian M

ass

exti

nct

ion

Mas

sex

tin

ctio

n

Mas

sex

tin

ctio

n

Echinoderms(sea stars, seaurchins) diversify

Coralreefsexpand

First upland plantcommunities(evergreen forests),diversification of fish,emergence ofamphibians

Insects diversify,coal-forming swampsabundant, sharksabundant, radiationof amphibians

Coal-forming swampsdiminish; parts ofAntarctica forested

Supercontinent Pangeaassembles. Building ofAppalachian Mountains ends.Climate warm; little variation.

Supercontinent of Laurentiato the north and Gondwanato the south. Climate mild.

Climate cold;extensive icein Gondwana.

Supercontinent of Gondwanaforms. Oceans cover much ofNorth America. Climate notwell known.

Laurentia

Gondwana

Pangea

GondwanaGondwana

Figure 27-8c

Phanerozoic Eon: The Mesozoic Era is sometimes called the Age of Reptiles.

First n

ecta

r-drin

king in

sect

s

Triasssic

Gymnosperms become dominantland plants; extensive deserts

Mas

sex

tin

ctio

n

First d

inosa

urs

First m

amm

als

First t

yran

nosaurid

din

osaur

First a

ngiosp

erm

(flo

wer

ing p

lant)

First b

ird (A

rchae

optery

x)Firs

t cen

tric

diato

ms

First w

ater

lilie

s

First m

agnolia

-fam

ily p

lants

First b

ee; f

irst a

nt

First p

lace

ntal m

amm

als

Mas

sex

tin

ctio

n

Jurassic Mas

sex

tin

ctio

n

Cretaceous

Gymnosperms continueto dominate land

Dinosaurs diversify Flowering plants diversify

Pangea intact. Interiorof Pangea arid. Climatevery warm.

Pangea begins to break apart;interior of continent still arid.

Gondwana begins to breakapart; interior less arid.

India separated from Madagascar,moves north; Rocky Mountainsform. Climate mild, temperate.

Pan

gea

Pan

gea Gondwana

Figure 27-8d

Phanerozoic Eon: The Cenozoic Era is nicknamed the Age of Mammals.

First h

orses

Paleogene

Continents continue to drift apart.Collision of India with Eurasia begins.Australia moves north from Antarctica.Palms in Greenland and Patagonia.

First p

rimat

es

First f

ully a

quatic

whal

es

First a

pes

Old

est p

ollen fr

om

d

aisy

-fam

ily p

lants

Earlie

st h

omin

ins

Homo

s

apie

ns

Paleocene Eocene Oligocene

Neogene

Miocene Pliocene Pleistocene

Diversification of grazing mammalsDiversification of angiospermsand pollinating insects

Diversification ofmammalian orders

Strong drying trend inAfrica and other continents;grasslands form. Alps andHimalayas begin to rise.

Continents close to presentposition. Beginning ofAntarctic ice cap. Openingof Red Sea.

North and South Americajoined by land bridge.Uplift of the Sierra Nevada.Worldwide glaciation.

http://vathena.arc.nasa.gov/curric/land/global/climchng.html

These two figures show former temperatures with major periods of glaciation labeled. The dashed lines are the present global average temperature of about 15° C (59° F). Thus the solid curves show small changes from this average; note that the temperature drops only about 5° C during a glaciation. This has occurred about every 100,000 years, with smaller wiggles in between. That is, there has been a 100,000 year glaciation cycle for the past million years or so, and there may be shorter cycles as well.

http://www.public.iastate.edu/~alloquep/eco/geoHist.html

http://www.public.iastate.edu/~alloquep/eco/geoHist.html