1 Chapter 26 Lecture Outline Copyright © McGraw-Hill Education. Permission required for reproduction or display. See separate PowerPoint slides for all

1

Chapter 26Lecture Outline

Copyright © McGraw-Hill Education. Permission required for reproduction or display .

See separate PowerPoint slides for all figures and tables pre-inserted into PowerPoint without notes.

This chameleon species (Furcifer labordi) has the shortest life cycle of any known land vertebrate, just 4–5 months at most

3

Chapter 26Animal Diversity: The Vertebrates

Vertebrates: Chordates with a Backbone

Gnathostomes: Jawed Vertebrates

Tetrapods: Gnathostomes with Four Limbs

Amniotes: Tetrapods with a Desiccation-Resistant Egg

Mammals: Milk-Producing Amniotes

Chapter Outline:

Have chordate features as well as

1. Vertebral column

2. Cranium

3. Endoskeleton of cartilage or bone

4

Vertebrates: Chordateswith a Backbone

5

Cy

clo

sto

ma

ta (

lam

pre

ys a

nd

ha

gfi

sh

)

Ch

on

dri

ch

thy

es (

cart

ilag

ino

us

fish

es)

Ac

tin

op

tery

gii

(ray

-fin

ned

fis

hes

)

Sar

cop

tery

gii

(lo

be-

fin

ne

d f

ish

es)

Am

ph

ibia

(am

ph

ibia

ns

)

Re

pti

lia

(tu

rtle

s, l

izar

ds,

sn

akes

,c

roc

od

iles

, bir

ds)

Mam

mal

ia (

ma

mm

als

)

Critical innovations

KEY

Milk,hair

Amniotic egg

Limbs

Lobed fins

Bony skeleton, lungsor lung derivatives

Jaws

Vertebral column, cranium,endoskeleton

Ancestral vertebrate

Vertebrates

Gnathostomes

Osteichthyans

Lobefins

Tetrapods

Amniotes

Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

6

Cy

clo

sto

ma

ta (

lam

pre

ys

an

d h

ag

fis

h)

Ch

on

dri

ch

thy

es

(c

art

ila

gin

ou

s f

ish

es

)

Ac

tin

op

tery

gii

(ra

y-f

inn

ed

fis

he

s)

Sa

rco

pte

ryg

ii (

lob

e-f

inn

ed

fis

he

s)

Am

ph

ibia

(a

mp

hib

ian

s)

Re

pti

lia

(tu

rtle

s,

liza

rds

, s

na

ke

s,

cro

co

dil

es

, b

ird

s)

Ma

mm

ali

a (

ma

mm

als

)

Vertebrates

Gnathostomes

Osteichthyans

Lobefins

Tetrapods

Amniotes


Hagfish

Marine fish lackingjaws, fins or vertebrae

Secondary loss of vertebral columnincreased flexibility

Notochord and cartilaginous skull

Essentially blind with a keen sense of smell

Copious amounts of slime8

Lampreys

Lack hinged jaw and true appendages

Have a notochord and rudimentary vertebral column

9


Cy

clo

sto

ma

ta

Ch

on

dri

ch

thy

es

Ac

tin

op

tery

gii

Sa

rco

pte

ryg

ii

Am

ph

ibia

Re

pti

lia

Ma

mm

ali

a


One of earliest diverging groups of vertebrates Found in marine and freshwater Marine lampreys parasitic as adults

10

(a) Jawless mouth of a sea lamprey (b) A sea lamprey feeding


a: © Breck P. Kent/ Animals Animals; b: © Jacana/Photo Researchers, Inc.

Hinged jaws developed from the pharyngeal arches

Evolution modified an existing feature to form the jaw Some gill arches were lost, some modified

11

Gnathostomes:Jawed Vertebrates

12

BIOLOGY PRINCIPLE

Structure determines function

The development of a jaw increased the predatory capabilities of gnathostomes.

13


Class Chondricthyes

Sharks, skates, rays

Cartilaginous fish Skeleton of flexible cartilage Derived character within the

Chondrichthyes (not ancestral) Developmental change prevented

ossification of cartilage

Sharks among earliest fish to develop teeth But teeth are not set into jaw

14


Cyc

lost

om

ata

Ch

on

dri

chth

yes

Act

ino

pte

ryg

ii

Sar

cop

tery

gii

Am

ph

ibia

Rep

tili

a

Mam

ma

lia


Denser than water – must keep swimming to maintain buoyancy and breathing

Dual-chambered heart – single circulation

Powerful sense of smell

Lateral line – pressure wave detection

Internal fertilization Oviparous – lay eggs Ovoviparous – egg retained in female, no placenta Viviparous – eggs develop in uterus, placenta

nourishes young15

16

Copyright © McGraw-Hill Education. Permission required for reproduction or display.

Caudal fin Dorsal fin

Pelvic fin Pectoral fin

(a) Silvertip shark

(b) Stingray

(c) Rows of shark teeth

(d) Shark egg poucha: © Valerie & Ron Taylor/ardea.com; b: © Bill Curtsinger/National Geographic/Getty Images; c: © Jeff Rotman/naturepl.com; d: © Oxford Scientific/Getty Images

Osteichthyans

Bony fish Actinopterygii – ray-finned fish Sarcopterygii – lobe-finned fish

Coelacanths, lungfish – and tetrapods!

Three features distinguishfrom Chondricthyes1. Bony skeleton

2. Operculum covering gills

3. Swim bladder for buoyancy

17

Actinopterygii – ray-finned fish Includes all bony fish except coelocanths and lungfish Fins supported by thin, bony, flexible rays

18

Sarcopterygii – lobe-finned fish Actinistia – coelacanths Dipnoi – lungfish Tetrapods (terrestrial vertebrates)

Since tetrapods evolved from lobe-finned fish, the group Sarcopterygii has been expanded to include both lobe-finned fishes and tetrapods

Fins are supported by skeletal extensions of the pectoral and pelvic areas that are moved by muscles within the fins

19

Transition to land in Devonian involved adaptations for locomotion, reproduction, and to prevent desiccation

Sturdy lobe-finned fishes became animals with four limbs

Vertebral column strengthened, hip and shoulder bones braced against backbone

Relatively simple changes in gene expression, especially Hox genes

20

Tetrapods: Gnathostomeswith Four Limbs

Davis and colleagues provide a genetic-developmental explanation for limb length in tetrapods

Specific Hox genes are responsible for determining limb formation in mice

Mutations in the genes HoxA-11 and HoxD-11 resulted in the loss of the radius, ulna, and some of the carpals

Relatively simple mutations can control relatively large changes in limb development

FEATURE INVESTIGATION


AD

AD

Ad

Ad

aD

aD

ad

ad

AADD

AADD

AADd

AaDD

AaDd

AADd

AAdd

AaDd

Aadd

AaDD

AaDd

aaDD

aaDd

AaDd

Aadd

aaDd

aadd

aadd

9:3:3:1 phenotypic ratio expected in a dihybrid cross

Experimental level Conceptual level

2

3

1

GOAL To determine what role Hox genes have in limb development in mice.

KEY MATERIALS Mice with individual mutations in HoxA- 11 and HoxD- 11 genes.

Breed mice with individual mutations inHoxA-11 and HoxD-11 genes. (The A andD refer to wild-type alleles; a and daremutant alleles.)

Using molecular techniques describedin Chapter 20, obtain DNA from the tailand determine the genotypes ofoffspring.

Stain the skeletons and compare thelimb characteristics of the wild-typemice (AADD) to those of strains carrying mutant alleles in one or both genes.

The mice bred were heterozygous for both genes(AaDd).

AaDdmice

Based on previous studies, researchersexpect mutant mice to produce viableoffspring, perhaps with altered limbmorphologies.

The resulting genotypes would occur inMendelian ratios, generating mice withdifferent combinations of wild-type andmutant alleles.

Mutant mice may havealtered bone morphologies.

Doublemutant


4

AADD

AaDD

Carpal bone fusions (% of mice showing the fusion)

THE DATA

Genotype Normal (none fused) NL fused to T

17

T fused to P

50

NL fused to T and P

aaDD

AADd

AAdd

100

100

33

100

0

0

0

0

0

0

0

0

0

0

17

170

17

17

33

67

33AaDd

5 CONCLUSION Relatively simple mutations involving two genes can cause large changes in limb development.

6 SOURCE Davis, P.A. et al. 1995. Absence of radius and ulna in mice lacking Hoxa-11 and Hoxd-11. Nature 375:791–795.



Amphibians

Successfully invaded land but must return to water to reproduce

Buccal pumping to force air into lungs

Skin can absorb oxygen

3 chambered heart

Fertilization external

Larval stages aquatic

Metamorphosis regulated by thyroid24


Cyc

lost

om

ata

Ch

on

dri

chth

yes

Act

ino

pte

ryg

ii

Sar

cop

tery

gii

Am

ph

ibia

Rep

tili

a

Mam

ma

lia


Order Anura – frog and toads Nearly 90% of amphibians Carnivorous adults, herbivorous larva

Order Urodela – salamanders Paedomorphosis – adult has larval characteristics

Order Apoda – caecilians Nearly blind tropical burrowers Secondarily legless Uterine milk nourishes young inside mother’s body

25

26

27


(a) Tree frog

(b) A caecilian (c) Mud salamandera: © Gregory G. Dimijian/Photo Researchers,Inc.; b: © Juan-Manuel Renjifo/agefotostock;

c: © Gary Meszaros/Photo Researchers, Inc.

Critical innovation was the development of a shelled egg that sheltered the embryo from desiccating conditions on land

Amniotic egg gave independence from water

28

Amniotes: Tetrapods with a Desiccation-Resistant Egg


Cy

clo

sto

ma

ta

Ch

on

dri

ch

thy

es

Ac

tin

op

tery

gii

Sa

rco

pte

ryg

ii

Am

ph

ibia

Re

pti

lia

Ma

mm

ali

a


29

Other key innovations Desiccation-resistant skin Thoracic breathing – negative pressure sucks air in Water-conserving kidneys – concentrate waste prior

to elimination Internal fertilization

Traditional classification has three living amniotes – reptiles, birds and mammals Birds are now considered part of reptilian lineage

30

Class Testudines

Turtles, tortoises and terrapins

Virtually unchanged for 200 million years

Hard protective shell

In most, vertebrae and ribs fused to shell

Lack teeth but have sharp beak

31


(a) Green turtlea: © Pat Morris/ardea.com

Class Squamata

Lizards and snakes

Kinetic skull with extremely mobile joints

Lizards have moveable eyelids and external ears while snakes do not

32

33

Class Crocodilia Crocodiles and alligators Essentially unchanged for 200 million years 4 chambered heart Teeth in sockets Care for young

34

Archaeopteryx lithographica

A transitional specieswith both dinosaur features and bird features like wings and feathers

Related to therapods, group of saurischian dinosaurs

Class Aves

Four features unique to birds (for flight):

1. Feathers – modified scales keep birds warm and enable flight

2. Air sacs – very efficient breathing

3. Reduction of organs – single ovary, no urinary bladder

4. Lightweight bones – thin, hollow, honeycombed Sternum to anchor flight muscles, no teeth 36

BIOLOGY PRINCIPLE

Structure determines function

Each of these beak shapes permits a different method of feeding.


(a) Cracking beak (b) Scooping beak (c) Tearing beak

(f) Sieving beak

(d) Probing beak (e) Nectar-feeding beak

a: © B. G. Thomson/Photo Researchers, Inc.; b : © Jean-Claude Canton/Bruce Coleman Inc./ Photo shot; c: © Morales/agefotostock; d: © Brand X Pictures/PunchStock RF; e: © Rick& Nora Bowers/Visuals Unlimited; f: ©MervynRees/Alamy

Birds also have Warm body temperature Double circulation with 4 chambered heart Acute vision Most carnivores Eggs brooded Complex courtship

28 orders, 166 families, 9600 species

38

Evolved from amniote ancestors earlier than birds

Appeared about 225 mya

After dinosaur extinction mammals flourished

Range of sizes and body forms unmatched

39

Mammals: Milk-Producing Amniotes


Cy

clo

sto

ma

ta

Ch

on

dri

ch

thy

es

Ac

tin

op

tery

gii

Sa

rco

pte

ryg

ii

Ma

mm

ali

a

Am

ph

ibia

Re

pti

lia


40

Distinguishing characteristics: Mammary glands secrete milk

All mammals have hair (more or less)

Only vertebrates with specialized teeth

Enlarged skull Brain enlarged in large skull Single lower jaw bone 3 inner ear bones External ears

41

42

(b) Camouflaged coat(a) Sensory hairs (c) Defensive quills


a: © Eric Baccega/agefotostock; b:© Charles Krebs/Corbis; c: © Anthony Bannister/Photo Researchers, Inc.

43


(a) Biting teeth (b) Grinding teeth (c) Gnawing teeth

(d) Tusks (e) Grasping teetha: © Image Source/CorbisRF; b: © Joe McDonald/Corbis; c: © mauritiusimages GmbH/Alamy; d: © DLILLC/Corbis RF;

e: © Ken Lucas/Visuals Unlimited

Subclass Prototheria – Monotremes Platypus and echidna lay eggs, lack placenta,

poorly developed nipples

Subclass TheriaClade Metatheria - Marsupials

7 ordersOnce widespread, now confined mostly to

AustraliaOpossum found in North AmericaVery undeveloped young must make it to

marsupium to finish development

44

45

Subclass Theria – Clade Eutheria Placental mammals Long-lived complex placenta Prolonged gestation

46

Primates

Primarily tree-dwelling species

Evolved about 85 mya

Defining characteristics Grasping hands with opposable thumbs Large brain Some digits have flat nails (not claws) Binocular vision Complex social behavior, well-developed parental care

47

48


Hominoidea

Anthropoidea

HaplorrhiniStrepsirrhini

Bu

sh b

abie

s,le

mu

rs,

po

tto

s

Mo

nke

ys

Gib

bo

ns

Go

rilla

s

Ch

imp

anze

es

Hu

man

s

Ora

ng

uta

ns

Tars

iers

Su

bfa

mily

Po

ng

inae

Trib

e G

ori

llin

i

Fam

ily H

ylo

bat

idae

Trib

e H

om

inin

i

Trib

e P

anin

i

Su

bfa

mily

Ho

min

inae

Fam

ilyH

om

inid

ae

Strepsirrhini – wet noses (no fur at tip) Bush babies, lemurs, pottos Generally nocturnal and smaller-brained

Haplorrhini – dry noses (furry) Tarsiers Anthropoidea

Monkeys Hominoidea - gibbons, gorillas, orangutans,

chimpanzees and humans

49

50


(a) Strepsirrhini (lesser bush baby) (b) Anthropoidea (capuchin monkey) (c) Hominoidea (white-handed gibbon)a: © David Haring/DUPC/Getty Images; b: © Gerard Lacz/Animals Animals; c: © Martin Harvey/Corbis

MonkeysTails, usually smaller

Hominoids – gibbons, gorillas, orangutans, chimpanzees and humansNo tails, usually largerMobile shoulder joints, broader rib cages, and

a shorter spine – help swinging in treesFamily Hylobatidae – lesser apes or gibbonsFamily Hominidae – greater apes

51

52

Humans are related to chimpanzees and apes but did not evolve directly from them

All hominoids shared a common ancestor

Family Hominidae Subfamily Ponginae – orangutans Subfamily Homininae

Tribe Gorillini – gorillas Tribe Panini – chimpanzees Tribe Hominini– humans and their ancestors

53

Comparing the human and chimpanzee genetic codes

Compared human and chimp genomes

Differ by only 1.23% 10 times less than mouse and rat genome

Many differences result from inversions and duplications

Differences may explain why humans susceptible to some diseases that chimps are not

May have been interbreeding after initial split

EVOLUTIONARY CONNECTIONS

Human evolution

About 6 mya in Africa, ancestral human lineage split off from primate lineage

Human evolution can be visualized like a tree, with one or two hominin species coexisting Some eventually went extinct, others gave rise to

other species Evolution is not a neat progression

Key characteristic was bipedalism Resulted in many changes – spine sits

underneath skull, broader pelvis, lower limbs larger

Australopithecines – widespread, at least six species, relatively small, facial structure and brain size similar to chimp

Homo – increased brain size, stone tools Homo sapiens 30,000 years ago Taller, lighter-weight, slightly smaller brain capacity than

H. neanderthalensis Out of Africa hypothesis supported over multiregional

hypothesis

56

57


0

Time

Millions of years ago (mya)

5.0 4.0 3.0 2.0 1.0

H. neanderthalensisH. heidelbergensisParanthropus boisei

Paranthropusrobustus

H. ergaster

Homohabilis

A. africanus

A. garhi

Australopithecus afarensis(“Lucy”)

Homosapiens

H. erectus

Ardipithecineancestor(bipedalism)

58


“Eve”

30°N

30°S

Equator

ca. 170,000–150,000 years ago

100,000

67,000

40,000

40,000

20,000

15,000

Documents

1 Chapter 26 Lecture Outline Copyright © McGraw-Hill Education. Permission required for reproduction or display. See separate PowerPoint slides for all