Ch30 (2)

Chapter 30

Chapter 30

ANIMALS

ANIMALS

Six Kingdoms are usually recognized: Prokaryota, Archaea, Protoctista, Fungi, Plantae and Six Kingdoms are usually recognized: Prokaryota, Archaea, Protoctista, Fungi, Plantae and  Animalia

 Animalia !he "ord

!he "ord animalanimal comes #rom the $atin %anima%, "hich means soul or &reath comes #rom the $atin %anima%, "hich means soul or &reath !he #ollo"ing notes ha'e

!he #ollo"ing notes ha'e &een taken &een taken #rom the &ook #rom the &ook &y (argulis and &y (argulis and Sch"artz, Sch"artz, %Fi'e%Fi'e Kingdoms%, 3rd )dition, *++

Kingdoms%, 3rd )dition, *++

•

•  Animals are heterotro Animals are heterotrophic, diplphic, diploid, multiceloid, multicellular organlular organisms that usisms that usually -exceually -except. spongpt. sponges.es.

de'elop #rom a &lastula de'elop #rom a &lastula

•

• !he &lastula, a multicellular em&ryo that de'elops #rom the diploid zygote produced &y!he &lastula, a multicellular em&ryo that de'elops #rom the diploid zygote produced &y

#ertilization o# a large diploid egg &y a smaller haploid sperm, is uni/ue to animals #ertilization o# a large diploid egg &y a smaller haploid sperm, is uni/ue to animals

•

• !he gametes o# animals, eggs and sperms, di##er in size and #orm and are called!he gametes o# animals, eggs and sperms, di##er in size and #orm and are called

anisogametes anisogametes

ther characteristics that can &e added to those a&o'e are: eukaryotes, "ith cells specialized ther characteristics that can &e added to those a&o'e are: eukaryotes, "ith cells specialized and organized into tissues, organs, etc1 they inha&it the sea, #resh "ater and land1 most are and organized into tissues, organs, etc1 they inha&it the sea, #resh "ater and land1 most are capa&le o# locomotion at some stage o# their li'es1 most can respond adapti'ely to external capa&le o# locomotion at some stage o# their li'es1 most can respond adapti'ely to external stimuli and ha'e "ell de'eloped sense organs and ner'ous system1 most reproduce sexually, stimuli and ha'e "ell de'eloped sense organs and ner'ous system1 most reproduce sexually, "ith large non2motile eggs and small #lagellated sperms !he diploid zygote produced &y "ith large non2motile eggs and small #lagellated sperms !he diploid zygote produced &y #ertilization di'ides &y mitotic di'isions, resulting in a &all o# cells that usually hollo"s out to #ertilization di'ides &y mitotic di'isions, resulting in a &all o# cells that usually hollo"s out to &ecome a &lastula

&ecome a &lastula

!he kingdom Animalia is di'ided into a&out 3 phyla -sing phylum. !he kingdom Animalia is di'ided into a&out 3 phyla -sing phylum.

Phyla are distinguished #rom each other &y the &ody plan, the ma4or #eatures o# its structural Phyla are distinguished #rom each other &y the &ody plan, the ma4or #eatures o# its structural and #unctional design

and #unctional design

THE ARCHITECTURE OF ANIMALS. THE ARCHITECTURE OF ANIMALS.

Four #eatures are commonly used to distinguish the &ody plan o# animals: Four #eatures are commonly used to distinguish the &ody plan o# animals:

*

* !h!he e nunum&m&er er o#o# tissue layerstissue layers #ound in the em&ryo: diplo&last or triplo&last #ound in the em&ryo: diplo&last or triplo&last 5

5 !h!he e tytyppe e oo## body symmetrybody symmetry: radial or : radial or &ilateral&ilateral 3

3 PresPresencence or ae or a&se&sence nce o# a o# a &ody &ody #lui#luid2#ild2#illedled body a!itybody a!ity: acoelomates,: acoelomates, pseudocoelomates, or coelomates

pseudocoelomates, or coelomates 6

6 !h!he pe patattetern rn o#o# early embryoni de!elo"mentearly embryoni de!elo"ment: protostomes or deuterostomes: protostomes or deuterostomes Embryoni tissues.

Embryoni tissues.  A

 A tissue is atissue is an organizn organized and #ued and #unctionalnctionally integrately integrated group od group o# cells# cells #i"loblasts

7n

7n tri"loblaststri"loblasts there are three layers present, the there are three layers present, the endodermendoderm, the, the mesodermmesoderm and the and the etoderm

etoderm

$ody symmetry. $ody symmetry.  A

 A &ody is sy&ody is symmetrical i# it cmmetrical i# it can &e di'an &e di'ided in a ided in a "ay that "ay that results in siresults in similar sidesmilar sides Asymmetry

Asymmetry !hey cannot &e section in a "ay that produces similar parts Some sponges are !hey cannot &e section in a "ay that produces similar parts Some sponges are asymmetrical

asymmetrical Radial symmetry

Radial symmetry has t"o planes o# symmetry1 the &ody is shaped like a cylinder or a disk "ith has t"o planes o# symmetry1 the &ody is shaped like a cylinder or a disk "ith parts radiating #rom a central point

parts radiating #rom a central point $ilateral symmetry

$ilateral symmetry has only one plane o# symmetry di'iding the &ody into t"o sides, le#t and has only one plane o# symmetry di'iding the &ody into t"o sides, le#t and right1 the &ody is usually long and narro" "ith a head and tail

right1 the &ody is usually long and narro" "ith a head and tail !ypes o# sectioning a specimen:

!ypes o# sectioning a specimen:

•

• Sagittal setion di'ides the &ody intoSagittal setion di'ides the &ody into rig%t and le&t "artsrig%t and le&t "arts •

• Cross or trans!erse setionCross or trans!erse setion di'ides the &ody into di'ides the &ody into anterior and "osterior "artsanterior and "osterior "arts •

• Frontal setion di'ides the &ody intoFrontal setion di'ides the &ody into dorsal and !entral "artsdorsal and !entral "arts

 All triplo&l

 All triplo&lastic animalastic animals ha'e &ilas ha'e &ilateral symmeteral symmetry, try, except the except the adult #orm adult #orm o# the eo# the echinodechinoderms, egrms, eg star#ish

star#ish

8ilateral symmetry is the most common !he reason #or this is 8ilateral symmetry is the most common !he reason #or this is

•

• 9nidirectional mo'ement o# the animal #or &etter sensing the en'ironment -senses on9nidirectional mo'ement o# the animal #or &etter sensing the en'ironment -senses on

the head., and easier to #ind #ood the head., and easier to #ind #ood

•

• ith the mesoderm, ner'ous and muscular systems de'eloped allo"ing directionalith the mesoderm, ner'ous and muscular systems de'eloped allo"ing directional

mo'ement possi&le mo'ement possi&le

$ody a!ity $ody a!ity  Animals may  Animals may &e&e

•

• AoelomateAoelomate: lack coelom or &ody ca'ity, eg cnidarians, ctenophores, #lat"orms: lack coelom or &ody ca'ity, eg cnidarians, ctenophores, #lat"orms •

• 'seudooelomate('seudooelomate(  coelom is partially lined "ith mesoderm, eg round"orms, roti#ers coelom is partially lined "ith mesoderm, eg round"orms, roti#ers •

• CoelomateCoelomate: coelom is completely lined "ith mesoderm: coelom is completely lined "ith mesoderm

;iplo&last lack a &ody ca'ity !riplo&lasts ha'e either a #alse coelom or a true coelom ;iplo&last lack a &ody ca'ity !riplo&lasts ha'e either a #alse coelom or a true coelom  Ad'anta

 Ad'antages o# thges o# the coelom:e coelom:

•

• Pro'ides space #or many organs to #unction "ith #reedom, eg heart, gonadsPro'ides space #or many organs to #unction "ith #reedom, eg heart, gonads •

•  Allo"s the  Allo"s the digesti'e cdigesti'e ca'ity to moa'ity to mo'e inde'e independentlpendently o# &ody y o# &ody mo'ementsmo'ements •

•

• Coelomic #luid transports oxygen, "astes, etc to organs and tissuesCoelomic #luid transports oxygen, "astes, etc to organs and tissues

Early embryoni de!elo"ment in oelomates. Early embryoni de!elo"ment in oelomates.

Coelomate animals are &ilaterally symmetrical, except adult echinoderms, and triplo&lastic Coelomate animals are &ilaterally symmetrical, except adult echinoderms, and triplo&lastic Coelomates can &e di'ided into protostomes and deuterostomes

Coelomates can &e di'ided into protostomes and deuterostomes

!he 'ast ma4ority o# animals are protostomes, e g insects, mollusks, and segmented "orms !he 'ast ma4ority o# animals are protostomes, e g insects, mollusks, and segmented "orms Protostomes

Protostomes

•

• <a'e spiral clea'age o# the 'ery early em&ryo<a'e spiral clea'age o# the 'ery early em&ryo •

• !he pore #ormed during gastrulation &ecomes the mouth!he pore #ormed during gastrulation &ecomes the mouth •

• Coelom is #ormed in the mesoderm: schizocoelyCoelom is #ormed in the mesoderm: schizocoely •

• Protostomes also ha'e aProtostomes also ha'e a determinatedeterminate clea'age in "hich the #ate o# the em&ryonic cells clea'age in "hich the #ate o# the em&ryonic cells

is #ixed 'ery early in de'elopment is #ixed 'ery early in de'elopment ;euterostomes

;euterostomes

•

• <a'e radial clea'age<a'e radial clea'age •

• !he pore #ormed during gastrulation &ecomes the anus!he pore #ormed during gastrulation &ecomes the anus •

• (esoderm #orms pockets #rom the "all o# the digesti'e ca'ity and (esoderm #orms pockets #rom the "all o# the digesti'e ca'ity and pinch o## to #orm pinch o## to #orm thethe

coelom: enterocoely coelom: enterocoely

•

• ;euterostomes ha'e an;euterostomes ha'e an indeterminateindeterminate clea'age in "hich each cell keeps longer the clea'age in "hich each cell keeps longer the

capacity to de'elop into a #ull organism capacity to de'elop into a #ull organism E!olutionary %y"ot%esis

E!olutionary %y"ot%esis

7t is &ased on the sharing o# the &asic &ody plan characters 7t is &ased on the sharing o# the &asic &ody plan characters  Acoeloma

 Acoelomates e'ol'ed tes e'ol'ed #irst, the #irst, the pseudocpseudocoelomates oelomates and the cand the coelomateoelomatess  A#ter the

 A#ter the coelom e'coelom e'ol'ed, theol'ed, then the pn the protostomes rotostomes split #rom dsplit #rom deuterostoeuterostomes, then mes, then the echinthe echinodermsoderms re'erted to an adult "ith radial symmetry although the lar'a is &ilateral

re'erted to an adult "ith radial symmetry although the lar'a is &ilateral 8ilateral coelomates then split into protostomes and deuterostomes 8ilateral coelomates then split into protostomes and deuterostomes

Segmentation e'ol'ed independently in &oth protostomes and deuterostomes Segmentation e'ol'ed independently in &oth protostomes and deuterostomes

Moleular "%ylogenies Moleular "%ylogenies

7s &ased on r=>A data 7t is still in progress 7s &ased on r=>A data 7t is still in progress

!entati'e results suggests that the &ranching &ased on r=>A studies is 'ery similar to the !entati'e results suggests that the &ranching &ased on r=>A studies is 'ery similar to the &ranching o# the phylogenetic tree &ased in &ody plan

&ranching o# the phylogenetic tree &ased in &ody plan

FEE#IN) FEE#IN)

!he #eeding tactics o&ser'ed in animals can &e di'ided into #i'e general types !he #eeding tactics o&ser'ed in animals can &e di'ided into #i'e general types *

* Sus"ension &eedingSus"ension &eeding

!he #iltering o# #ood suspended in "ater 7t is #ound only in a/uatic organisms !he #iltering o# #ood suspended in "ater 7t is #ound only in a/uatic organisms 7t is #ind in a "ide 'ariety o# animal groups, #rom shrimps, clams to "hales 7t is #ind in a "ide 'ariety o# animal groups, #rom shrimps, clams to "hales !his method o# #eeding has e'ol'ed many times in the animal kingdom !his method o# #eeding has e'ol'ed many times in the animal kingdom

*.

*. #e#e"o"osisit &et &eedediningg

;eposit #eeders eat their "ay through the su&strate ;eposit #eeders eat their "ay through the su&strate

!here are many types o# su&strates: soil, mud, mesophyll o# lea'es, stem tissues, piles o# #eces, !here are many types o# su&strates: soil, mud, mesophyll o# lea'es, stem tissues, piles o# #eces, and carcasses o# dead animals are &ut a #e" examples

and carcasses o# dead animals are &ut a #e" examples

!he #ood consists o# &acteria, #ungi, protists, and &its o# organic material -detritus. !he #ood consists o# &acteria, #ungi, protists, and &its o# organic material -detritus. ;eposit #eeders are #ound in many groups o# animals round "orms, segmented "orms, ;eposit #eeders are #ound in many groups o# animals round "orms, segmented "orms, mollusks, insect lar'ae, etc

mollusks, insect lar'ae, etc

3

3 Herbi!oryHerbi!ory

<er&i'ory means #eeding on plants -syn phytophagous. <er&i'ory means #eeding on plants -syn phytophagous.

•

• <er&i'ory includes de#oliation and consumption o# nectar, pollen, #ruits and seeds<er&i'ory includes de#oliation and consumption o# nectar, pollen, #ruits and seeds •

• #e&oliation is the destruction o# lea'es, &ark, "ood, roots and sap#e&oliation is the destruction o# lea'es, &ark, "ood, roots and sap •

• 7t includes protozoans and animals that #eed on &acteria and algae7t includes protozoans and animals that #eed on &acteria and algae

 Animals th

 Animals that eat plaat eat plant parts ant parts and algand algae are callee are calledd %erbi!ores%erbi!ores !here is a great di'ersity o# mouthparts #ound in her&i'ores !here is a great di'ersity o# mouthparts #ound in her&i'ores

+

+.. ''rreeddaattiioonn

Predators are organisms that kill and eat animals Predators are organisms that kill and eat animals

!ypes o# predation: Sit2and2"ait method and pro"ler method !ypes o# predation: Sit2and2"ait method and pro"ler method <er&i'ores support carni'ores

<er&i'ores support carni'ores

,

,.. ''aararassititisismm

Parasitism is an o&ligatory association &et"een organism o# t"o di##erent species Parasitism is an o&ligatory association &et"een organism o# t"o di##erent species

7n this association one organism &ene#its, the

7n this association one organism &ene#its, the "arasite"arasite, and the other, the, and the other, the %ost%ost, su##ers &ut is, su##ers &ut is seldom killed

seldom killed

!he parasite #eeds o## the &ody o# the host, eg mos/uito sucks &lood, intestinal "orms, etc !he parasite #eeds o## the &ody o# the host, eg mos/uito sucks &lood, intestinal "orms, etc  A

 A hea'y lohea'y load o# paad o# parasites is anrasites is an in&etionin&etion and the outcome o# an in#ection is a and the outcome o# an in#ection is a diseasedisease

•

• Eto"arasites li'e on their host, eg liceEto"arasites li'e on their host, eg lice •

• Endo"arasites li'e in their hosts, eg 'irusesEndo"arasites li'e in their hosts, eg 'iruses

Parasitism has e'ol'ed in a "ide 'ariety o# taxonomic groups Parasitism has e'ol'ed in a "ide 'ariety o# taxonomic groups

-E INNO/A

-E INNO/ATIONS IN THE TIONS IN THE RA#IATION OF ARTHRO'O#S.RA#IATION OF ARTHRO'O#S.

!he largest and most di'erse phylum "ith o'er one million species #ound in all ha&itats !he largest and most di'erse phylum "ith o'er one million species #ound in all ha&itats

'er * million species ha'e already &een descri&ed and there are pro&a&ly millions more still 'er * million species ha'e already &een descri&ed and there are pro&a&ly millions more still "aiting disco'ery

"aiting disco'ery

!he num&er o# insect species is not kno"n1 the estimates range #rom 3 to 30 million species !he num&er o# insect species is not kno"n1 the estimates range #rom 3 to 30 million species 7mportant characteristics:

7mportant characteristics: *

* 8i8ilalateteraral syml symmemetrtryy 5

5 8ody segm8ody segmented intented into heado head, thorax an, thorax and a&dod a&domen1 in some men1 in some head anhead and thorax #ud thorax #use into se into aa cephalothorax

cephalothorax 3

3 CoelCoelom smalom small and #ill and #illed "led "ith #luith #luid and id and inteinternal ornal organrganss 6

6 ?ointed a?ointed appendappendages thages that #unctit #unction in loon in locomotion, comotion, #eeding #eeding or copulor copulatory orgaatory organsns 

 )x)xososkekeleletotonn

E0os1eleton E0os1eleton

!he exoskeleton is secreted &y the epidermis, and made o# protein, chitin, lipids and minerals !he exoskeleton is secreted &y the epidermis, and made o# protein, chitin, lipids and minerals 7n crustaceans the exoskeleton has deposits o# calcium car&onate #orming a shell around the 7n crustaceans the exoskeleton has deposits o# calcium car&onate #orming a shell around the animal

animal

Periodic molting o# the exoskeleton allo"s gro"th Periodic molting o# the exoskeleton allo"s gro"th

!he rigid exoskeleton pro'ides attachment points to muscles !he rigid exoskeleton pro'ides attachment points to muscles

Pairs o# muscles that "ork antagonistically and are inserted at speci#ic points mo'e lim&s and Pairs o# muscles that "ork antagonistically and are inserted at speci#ic points mo'e lim&s and other parts

other parts Limbs Limbs  Arthropod

 Arthropods use thes use their lim&s in loir lim&s in locomotion ocomotion o# di##eren# di##erent types1 t types1 "alk, #ly"alk, #ly, s", s"im, 4ump, &urim, 4ump, &urro", ro", etcetc !hey are made o# cylindrical or #lattened segments connected &y 4oints

!hey are made o# cylindrical or #lattened segments connected &y 4oints

!he lim&s o# arthropods appear to &e homologous !heir great di'ersi#ication occurred through !he lim&s o# arthropods appear to &e homologous !heir great di'ersi#ication occurred through natural selection and other e'olutionary processes

natural selection and other e'olutionary processes Inset metamor"%osis.

Inset metamor"%osis.

(etamorphosis is the change in structure and #orm undergone &y an animal as it de'elops #rom (etamorphosis is the change in structure and #orm undergone &y an animal as it de'elops #rom em&ryo to adult

em&ryo to adult

7nsects are a 'ery success#ul group o# organisms: exoskeleton, three &ody parts, three pairs o# 7nsects are a 'ery success#ul group o# organisms: exoskeleton, three &ody parts, three pairs o# legs and the a&ility to #ly

legs and the a&ility to #ly

7nsects undergo metamorphosis A series o# molts allo"s the insect to gro" and change 7nsects undergo metamorphosis A series o# molts allo"s the insect to gro" and change (etamorphosis could &e o# t"o types:

(etamorphosis could &e o# t"o types:

•

• Hemimetabolous, in "hich the 4u'enile resem&les the adult #orm, eg young cockroachHemimetabolous, in "hich the 4u'enile resem&les the adult #orm, eg young cockroach

and adult cockroach !he changes are minimal and adult cockroach !he changes are minimal

•

• Holometabolous, in "hich the early stages are 'ery di##erent #rom the adult, egHolometabolous, in "hich the early stages are 'ery di##erent #rom the adult, eg

caterpillar to &utter#ly 7t in'ol'es dramatic changes caterpillar to &utter#ly 7t in'ol'es dramatic changes

7n holometa&olous insects the di##erent stages do not compete "ith each other &ecause they 7n holometa&olous insects the di##erent stages do not compete "ith each other &ecause they occupy di##erent en'ironments

occupy di##erent en'ironments

7nsect de'elopment is controlled &y the interaction o# 'arious hormones 7nsect de'elopment is controlled &y the interaction o# 'arious hormones

•

• @enerally an en'ironmental #actor a##ects neuroendocrine cells in the &rain@enerally an en'ironmental #actor a##ects neuroendocrine cells in the &rain •

• 8rain secretes 8< hormone that stimulates the prothoracic gland to produce (<,8rain secretes 8< hormone that stimulates the prothoracic gland to produce (<,

molting %ormone or edysome

molting %ormone or edysome, "hich stimulates gro"th and molting, "hich stimulates gro"th and molting

•

• ?<, 4u'enile hormone, maintains the lar'al stage and pre'ents metamorphosis?<, 4u'enile hormone, maintains the lar'al stage and pre'ents metamorphosis •

• hen the ?< decreases the lar'a de'elops into a pupahen the ?< decreases the lar'a de'elops into a pupa •

• 7n the a&sence o# ?<, the pupa molts and &ecomes an adult7n the a&sence o# ?<, the pupa molts and &ecomes an adult •

• !he amount o# ?< decreases "ith each successi'e molt!he amount o# ?< decreases "ith each successi'e molt

-E INNO/A

-E INNO/ATIONS IN THE TIONS IN THE RA#IATION OF /ERTE$RATES.RA#IATION OF /ERTE$RATES. erte&rates are a su&phylum mem&ers o# phylum Chordata erte&rates are a su&phylum mem&ers o# phylum Chordata Classi&iation

P

P<<BB$$99( ( CC<<==;;AA!!AA SuSu&&pphhyylluum m 99rroocchhoorrddaattaa Su&phylum Cephalochordata Su&phylum Cephalochordata Su&phylum erte&rata

Su&phylum erte&rata C%ordates

C%ordates are coelomate animals "ith &ilateral symmetry, segmented &ody, "ith a tu&e2"ithin2 are coelomate animals "ith &ilateral symmetry, segmented &ody, "ith a tu&e2"ithin2 a2tu&e &ody plan and three "ell2de'eloped germ layers, an endoskeleton and closed circulatory a2tu&e &ody plan and three "ell2de'eloped germ layers, an endoskeleton and closed circulatory system !here are a&out 65,000 extant species

system !here are a&out 65,000 extant species

Chordates share "ith other phyla the #ollo"ing characteristics: coelomates "ith &ilateral Chordates share "ith other phyla the #ollo"ing characteristics: coelomates "ith &ilateral

symmetry, a tu&e2"ithin2a2tu&e &ody plan, endoskeleton, and a close circulatory system "ith a symmetry, a tu&e2"ithin2a2tu&e &ody plan, endoskeleton, and a close circulatory system "ith a 'entral heart

'entral heart

ther important characteristics are the presence o# 4a"s, mem&rane &ound egg, lim&s, and ther important characteristics are the presence o# 4a"s, mem&rane &ound egg, lim&s, and endothermy, the a&ility o# maintain a constant &ody temperature &y using the energy generated endothermy, the a&ility o# maintain a constant &ody temperature &y using the energy generated in meta&olic reactions

in meta&olic reactions

#istinguis%ing %arateristis o& C%ordates #istinguis%ing %arateristis o& C%ordates

*

* >>oototocchhoordrd

•

• Cartilaginous rod running underneath and supporting the ner'e cordCartilaginous rod running underneath and supporting the ner'e cord •

• =eplaced &y 'erte&rae in the adults o# many groups=eplaced &y 'erte&rae in the adults o# many groups

5

5 ;o;orsrsal al nener'r'e ce corordd

•

• Single, hollo", dorsal, a&o'e the notochordSingle, hollo", dorsal, a&o'e the notochord

3

3 PhPhararynyngegeal al slslititss

•

• Present in the em&ryo and adult o# some speciesPresent in the em&ryo and adult o# some species

6

6 PoPostst2a2ananal tal tailil

•

• Prominent in em&ryos o# all groups &ut not in all adultsProminent in em&ryos o# all groups &ut not in all adults

Com"arati!e a""roa%es. Com"arati!e a""roa%es. 2. Hemi%ordata

2. Hemi%ordata

•

• Small so#t2&odied coelomates "ith a pro&oscis, &ilaterally symmetrical, unsegmentedSmall so#t2&odied coelomates "ith a pro&oscis, &ilaterally symmetrical, unsegmented •

• @ill slits, "ith a ner'e cord that is not homologous "ith that o# chordates@ill slits, "ith a ner'e cord that is not homologous "ith that o# chordates •

• !hey lack a true notochord!hey lack a true notochord

*. Uro%ordates or asidians. *. Uro%ordates or asidians.

•

• $ar'al stage is chordate "ith gills, notochord and dorsal ner'e cord$ar'al stage is chordate "ith gills, notochord and dorsal ner'e cord •

• !hese structures are lost in the adult stage except #or the gill slits, "hich are present in the!hese structures are lost in the adult stage except #or the gill slits, "hich are present in the

adult adult

3. Ce"%alo%ordates or lanelets. 3. Ce"%alo%ordates or lanelets.

Share "ith the erte&rata the #ollo"ing characteristics: Share "ith the erte&rata the #ollo"ing characteristics:

•

• >otochord, gill slits, dorsal ner'e cord, metameric muscles, posterior direction o# &lood #lo">otochord, gill slits, dorsal ner'e cord, metameric muscles, posterior direction o# &lood #lo"

in the dorsal 'essel and anterior &lood #lo" in the 'entral 'essel, thyroid, homologous in the dorsal 'essel and anterior &lood #lo" in the 'entral 'essel, thyroid, homologous homeo&ox gene clusters $ar'a similar to the Agnatha

homeo&ox gene clusters $ar'a similar to the Agnatha

2 >otochord extends to the anterior end -cephalochordates. and does not end at 2 >otochord extends to the anterior end -cephalochordates. and does not end at a &rain

a &rain

•

•  Adults are suspens Adults are suspension #eedeion #eeders &urro"inrs &urro"ing in the seg in the sea &ottoma &ottom •

• )xample: 8ranchiostoma -DAmphioxus., lancelet)xample: 8ranchiostoma -DAmphioxus., lancelet

+. /ertebrates +. /ertebrates *

* eerte&ral rte&ral column column present1 present1 it replait replaces the ces the notochonotochord in rd in most spmost speciesecies 5

5 PronPronounounce cepce cephalihalizatization: "eon: "ell de'ell de'eloploped &raed &rainin 3

3 CranCranium eium encloncloses ases and pnd proterotects tcts the &he &rainrain 6

6 !"!"o po pairairs o# s o# apappependndagageses 

 (usc(uscles attles attachached to the eed to the endondoskelskeleton #eton #or mo'eor mo'emenmentt Moleular genetis

Moleular genetis  A

 A gene cagene called (anx lled (anx is in'ol'ed is in'ol'ed in the dein the de'elopmen'elopment o# the tat o# the tail muscles, il muscles, ner'e cord ner'e cord andand notochord

notochord

4a5s 4a5s  Agnath

 Agnathans -ostracoans -ostracoderms. apderms. appeared in peared in the late the late Cam&rian -0Cam&rian -0 my mya. ana. and did not d did not ha'e 4a"ha'e 4a"ss !he

!he OstraodermsOstraoderms "ere 4a"less #ish, "hich lacked paired appendages and "ere encased in "ere 4a"less #ish, "hich lacked paired appendages and "ere encased in &ony plates !heir internal skeleton "as made o# cartilage

&ony plates !heir internal skeleton "as made o# cartilage

!hese #ishes pro&a&ly o&tained their #ood &y s"allo"ing "ater rich in organisms and #iltering it !hese #ishes pro&a&ly o&tained their #ood &y s"allo"ing "ater rich in organisms and #iltering it "ith the help o# their gill

"ith the help o# their gill

>e" 4a"ed and #inned 'erte&rates arose during the mid2;e'onian -E30 mya. using hard >e" 4a"ed and #inned 'erte&rates arose during the mid2;e'onian -E30 mya. using hard &ony tissue #or structure and de#ense

&ony tissue #or structure and de#ense 8one is made o# a calcium phosphate salt 8one is made o# a calcium phosphate salt !he 4a"s originated #rom gill arches

!he 4a"s originated #rom gill arches

@ill arches are &ars o# cartilage that support the gill tissue @ill arches are &ars o# cartilage that support the gill tissue

!he gill2support hypothesis proposes that the #irst gill arch changed orientation and increased in !he gill2support hypothesis proposes that the #irst gill arch changed orientation and increased in size to produce the #irst 4a"

size to produce the #irst 4a"

?a"s and gill support cartilage are deri'ed #rom the same em&ryonic cells called the neural ?a"s and gill support cartilage are deri'ed #rom the same em&ryonic cells called the neural crest cells

crest cells

!he muscles that mo'e &oth structures are also deri'ed #rom the same em&ryonic group o# !he muscles that mo'e &oth structures are also deri'ed #rom the same em&ryonic group o# cells

cells

7t is an e'olutionary impro'ement that allo"s animal to hunt more e##iciently 7t is an e'olutionary impro'ement that allo"s animal to hunt more e##iciently Limbs

Limbs

Fossils o# #leshy2#ined #ish and early tetrapods are #rom the ;e'onian, a&out 3 million years Fossils o# #leshy2#ined #ish and early tetrapods are #rom the ;e'onian, a&out 3 million years ago

ago

=hipidistians, a group o# extinct #ishes, e'ol'ed pectoral and pel'ic appendages strong enough =hipidistians, a group o# extinct #ishes, e'ol'ed pectoral and pel'ic appendages strong enough and #lexi&le enough to ena&le them to lea'e drying pools to seek out those ponds that retained and #lexi&le enough to ena&le them to lea'e drying pools to seek out those ponds that retained "ater

"ater

=hipidistians &ecame extinct in the Permian -5+0256 mya. =hipidistians &ecame extinct in the Permian -5+0256 mya.

;ata #rom comparati'e anatomy and genetics suggest that tetrapod lim&s e'ol'ed #rom the #ins ;ata #rom comparati'e anatomy and genetics suggest that tetrapod lim&s e'ol'ed #rom the #ins o# #ish

o# #ish

!he num&er and arrangement o# the lim& &ones in the lim&s o# #leshy2#ined #ossil #ish and early !he num&er and arrangement o# the lim& &ones in the lim&s o# #leshy2#ined #ossil #ish and early tetrapod agree

tetrapod agree

8y the end o# the ;e'onian -3G0 mya. the transition #rom rhipidistian #ish to tetrapod 8y the end o# the ;e'onian -3G0 mya. the transition #rom rhipidistian #ish to tetrapod amphi&ian had occurred

amphi&ian had occurred

Some similarities &et"een early amphi&ians and =hipidistians are similar shape and position o# Some similarities &et"een early amphi&ians and =hipidistians are similar shape and position o# dermal skull &ones and homologous #ins and leg &ones

dermal skull &ones and homologous #ins and leg &ones T%e amnioti egg and endot%ermy

T%e amnioti egg and endot%ermy

!he hard2shelled egg is a ma4or e'olutionary inno'ation that appeared in the Car&oni#erous !he hard2shelled egg is a ma4or e'olutionary inno'ation that appeared in the Car&oni#erous

•

• 7t #irst appeared in re"tiles7t #irst appeared in re"tiles •

• 7t #rees the reptiles #rom reproducti'e dependence on "ater and allo"ed them to &ecome7t #rees the reptiles #rom reproducti'e dependence on "ater and allo"ed them to &ecome

#ully terrestrial #ully terrestrial

)ndothermy allo"s organisms to maintain a high &ody temperature using heat supplied &y the )ndothermy allo"s organisms to maintain a high &ody temperature using heat supplied &y the oxidation o# #ood

oxidation o# #ood

7t permits high le'el o# acti'ity in cold ha&itats and sustained #ast mo'ement 7t permits high le'el o# acti'ity in cold ha&itats and sustained #ast mo'ement $arge amount o# #ood is re/uired

)ctotherms are inacti'e or slo" in cold "eather and cannot maintain #ast mo'ement #or a long )ctotherms are inacti'e or slo" in cold "eather and cannot maintain #ast mo'ement #or a long time

time

@enetic studies in endothermic #ish suggest that endothermy e'ol'ed independently at least @enetic studies in endothermic #ish suggest that endothermy e'ol'ed independently at least three times in #ish and it is associated "ith cold ha&itats

three times in #ish and it is associated "ith cold ha&itats HUMAN E/OLUTION

HUMAN E/OLUTION

<ominids are mem&ers o# the

<ominids are mem&ers o# the &amily Hominidae&amily Hominidae, "hich includes se'eral species o#, "hich includes se'eral species o#  Australop

 Australophithecus ahithecus and <omond <omo

<umans -hominids. are adapted to &ipedal terrestrial locomotion and ha'eH <umans -hominids. are adapted to &ipedal terrestrial locomotion and ha'eH *

* $o$ongnger hier hind lind lim&s tm&s thahan #on #orelrelim&im&ss 5

5 Free hFree handands and s and re#ire#ined mned manianipulapulatory cotory controntroll 3

3 $a$arge &rge &rairain reln relatiati'e to &'e to &odody sizy sizee 6

6 SSmamall ll #a#accee 

 ShShorort ct cananinineses G

G $e$ess ss &o&ody dy hahairir 

 thether der dentantal anl and sd skelekeletal tal #ea#eatureturess

!hree species o# gracile australopithecines ha'e &een identi#ied !hree species o# gracile australopithecines ha'e &een identi#ied

•

• !hey li'ed in )ast A#rica #rom 6* to 56 million years ago!hey li'ed in )ast A#rica #rom 6* to 56 million years ago

 A&out th

 A&out three specieree species o# ro&us o# ro&ust australost australopithecinepithecines ha'e &es ha'e &een recogen recognizednized

•

• !hey li'ed in )ast A#rica &et"een 5 and *0 million years ago!hey li'ed in )ast A#rica &et"een 5 and *0 million years ago •

• !hese species had more massi'e teeth and 4a"s!hese species had more massi'e teeth and 4a"s

Out o& A&ria Out o& A&ria

!he earliest species o# <omo -< ha&ilis and < erectus. date #rom 56 to 50,000 million years !he earliest species o# <omo -< ha&ilis and < erectus. date #rom 56 to 50,000 million years ago

ago

(odern man, <omo sapiens, dates #rom a&out *30,000 years ago (odern man, <omo sapiens, dates #rom a&out *30,000 years ago

•

• For a&out 0,000 years therea#ter, < sapiens resided in A#rica, and < erectus inFor a&out 0,000 years therea#ter, < sapiens resided in A#rica, and < erectus in

 A#rica, an

 A#rica, and < nead < neanderthalenderthalensis in )uronsis in )uropepe

•

• 8y a&out 60,000 years ago, < erectus and < neanderthalensis had disappeared,8y a&out 60,000 years ago, < erectus and < neanderthalensis had disappeared,

and < sapiens occupied all o# )urasia and Australia and < sapiens occupied all o# )urasia and Australia !"o theories:

!"o theories: *

* <omo sapi<omo sapiens inter&reens inter&red "ith the d "ith the other t"other t"o species ao species and modern nd modern < sapie< sapiens is a &lens is a &lend o# thend o# the three species, original < sapiens, < erectus and < neanderthalensis

5

5 <omo sapi<omo sapiens originaens originated in ted in A#ricaA#rica, then migra, then migrated to oted to other parts ther parts o# the "o# the "orld !herorld !here "as noe "as no inter&reeding "ith other species o# <omo < sapiens outcompeted the other t"o species inter&reeding "ith other species o# <omo < sapiens outcompeted the other t"o species and remained the only sur'i'ing species

and remained the only sur'i'ing species

;>A studies support the hypothesis that the genus <omo e'ol'ed in A#rica and then migrated to ;>A studies support the hypothesis that the genus <omo e'ol'ed in A#rica and then migrated to )urope and Asia, e'entually to the >e" orld