Lecture 13: Animal ClassificationLecture 13: Animal Classification تصنيف تصنيفالحيوانالحيوان

SystematicSystematic includes taxonomy, which is the naming includes taxonomy, which is the naming تسميةتسمية and classification and classification تصنيفتصنيفof species and groups of species.of species and groups of species.

Taxonomy:Taxonomy: is that branch of biology dealing with the is that branch of biology dealing with the identificationidentificationتعريفتعريف and namingand namingتسميةتسمية of organisms.of organisms.

AristotleAristotle أرسطوأرسطو ((ancient Greek philosopherancient Greek philosopher) began the science of ) began the science of taxonomy.taxonomy.

Carolus LinneusCarolus Linneus كارلوس لينياسكارلوس لينياس((17001700ss) ) ((Swedish botanistSwedish botanist) classified ) classified all then-known organisms into two large kingdoms:all then-known organisms into two large kingdoms:

a) Kingdom Plantae a) Kingdom Plantae المملكة النباتيةالمملكة النباتية b) Kingdom Animaliab) Kingdom Animaliaالمملكة الحيوانيةالمملكة الحيوانية ..

Robert WhittakerRobert Whittaker in 1969 proposed five kingdoms: in 1969 proposed five kingdoms: Plantae, Plantae, Animalia, Fungi, Protista, and MoneraAnimalia, Fungi, Protista, and Monera..

Recent studies suggest that three domains be employed: Recent studies suggest that three domains be employed: Archaea, Bacteria, and EukaryaArchaea, Bacteria, and Eukarya

Systematic/Taxonomy Systematic/Taxonomy علم علم التصنيفالتصنيف

Animal TaxonomyAnimal TaxonomyLinneusLinneus classified species classified species النوعالنوعas the as the

smallest unit, and that each species smallest unit, and that each species nested within nested within يندرج تحتيندرج تحتa higher categorya higher category

SpeciesSpecies is a Latin word meaning is a Latin word meaning “kind” or “appearance“kind” or “appearanceالشكل الظاهريالشكل الظاهري ””..

Differentiation between species based Differentiation between species based on:on:

a)- Morphological differencesa)- Morphological differencesاختالفات شكليةاختالفات شكلية

b)- The potential to interbreedb)- The potential to interbreedالقدرة على التزاوجالقدرة على التزاوج with with eacheach other in nature other in nature to produce fertile offspringto produce fertile offspring جيل جيل خصيبخصيب

Traditional Classification Traditional Classification التصنيف التصنيفالتقليديالتقليدي

Traditional ClassificationTraditional Classificationالتصنيف التقليديالتصنيف التقليدي : depends : depends on both common ancestryon both common ancestry1سبالن1سب and the amount and the amount النof differences among groups.of differences among groups.

The traditionalThe traditional , dating to Linneaus view, is that , dating to Linneaus view, is that birds have feathersbirds have feathersريشريش , , reptiles have reptiles have scalesscalesحراشيفحراشيف , and , and mammals have hairmammals have hairشعرشعر ..

Linneus placed each of these groups in a Linneus placed each of these groups in a separate class within the Phylum Chordataseparate class within the Phylum Chordata شعبة شعبة

. . الحبلياتالحبليات

Binomial nomenclature Binomial nomenclature التسمية التسميةالثنائيةالثنائية

((االسم الثنائي للحيواناالسم الثنائي للحيوان))

LinneusLinneus developed the concept of developed the concept of binomial binomial nomenclaturenomenclature, whereby scientists could , whereby scientists could communicate clearly.communicate clearly.

Under the binomial system, each species is Under the binomial system, each species is assigned a two-part latinized nameassigned a two-part latinized name اسم التيني من اسم التيني من

:(:(a binomiala binomial) ,) , قسمينقسمين

1.1. The first partThe first part, the , the genusgenusالجنسالجنس , is the group to which a , is the group to which a species belongs.species belongs.

2.2. The second partThe second part, refers to the , refers to the speciesspeciesالنوعالنوع within the within the genus.genus.

3.3. The first letter of the genus is The first letter of the genus is capitalizedcapitalized and both and both names are names are italicizeditalicized andand latinizedlatinized..

4.4. For example, Linnaeus assigned to humans the scientific For example, Linnaeus assigned to humans the scientific name name HomoHomo sapienssapiens, which means “wise man”., which means “wise man”.

Systematic position of human Systematic position of human الوضع الوضعالتقسيمي لإلنسانالتقسيمي لإلنسان

KingdomKingdom: Animalia: Animaliaالمملكة الحيوانيةالمملكة الحيوانية PhylumPhylum: Chordata: Chordataشعبة الحبلياتشعبة الحبليات ClassClass: Mammalia: Mammaliaطائفة الثديياتطائفة الثدييات OrderOrder: Primates: Primatesرتبة الرئيسياترتبة الرئيسيات FamilyFamily: Hominidae: Hominidaeعائلة البشرعائلة البشر GenusGenus: : Homo Homo الجنس البشريالجنس البشري SpeciesSpecies:: sapiens sapiensاإلنساناإلنسان

Scientific name: Scientific name: HomoHomo sapienssapiens (The Wise Man (The Wise Man

((اإلنسان العاقلاإلنسان العاقل

EukaryotaEukaryota

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Three Kingdoms of lifeThree Kingdoms of life

There are three Kingdoms of life" There are three Kingdoms of life"

1)- 1)- BacteriaBacteria (Eubacteria),

2)- 2)- ArchaeaArchaea,

3)- Eukaryota 3)- Eukaryota ((Fungi, Protesta,Fungi, Protesta, Plantae & Animalia Plantae & Animalia))

Viruses are not considered living Viruses are not considered living organisms. organisms.

1- Prokaryotes1- Prokaryotes ( (bacteria & archaeabacteria & archaea))

Current taxonomy Current taxonomy recognizes two prokaryotic recognizes two prokaryotic domains domains ((KingdomsKingdoms)): domain : domain BacteriaBacteria and domain and domain ArchaeaArchaea..

Bacteria and archaea exist Bacteria and archaea exist so early in life and are very so early in life and are very different. different.

At the same time, theyAt the same time, theyboth are structurallyboth are structurallyorganized at theorganized at theprokaryotic level.prokaryotic level.

1- Prokaryotes (1- Prokaryotes (bacteria & archaeabacteria & archaea))Prokarytes exist in Prokarytes exist in

habitatshabitatsالبيئاتالبيئات that are that are too too cold, too hot, too salty, too cold, too hot, too salty, too acidic, or too alkalineacidic, or too alkaline for any for any eukaryote.eukaryote.

• Prokaryotes often interact with Prokaryotes often interact with other species of prokaryotes or other species of prokaryotes or eukaryotes with complementary eukaryotes with complementary metabolismsmetabolisms األيضي األيضي للتكامل .. للتكامل

• These relationships called (symbiosisThese relationships called (symbiosis المنفعة المنفعة تبادل :in three types:) in three types ( تبادل

1.1. CommensalismCommensalismالمعايشةالمعايشة : one partner receives benefits: one partner receives benefitsالمنفعةالمنفعة while the other is not harmed or helped by the relationship.while the other is not harmed or helped by the relationship.

2.2. ParasitismParasitismالتطفلالتطفل : one partner, the parasite, benefits at the : one partner, the parasite, benefits at the expense of the host.expense of the host.

3.3. MutualismMutualism المنفعة المنفعة تبادل .both partners benefit from each other. both partners benefit from each other :: تبادل

A)- ArchaeaA)- Archaea

Archaea are extremophiles, of extreme ”محب للظروف القاسية“environments and can be can be classified into:classified into:

a)- a)- Extreme halophilesExtreme halophilesمحب للملوحةمحب للملوحة :: live in such saline places as the live in such saline places as the

Great Salt Lake and the Dead Great Salt Lake and the Dead Sea.Sea.

Some species require an Some species require an extremely saltyextremely saltyشديدة الملوحةشديدة الملوحة environment to grow.environment to grow.

b)- b)- Extreme thermophilesExtreme thermophilesمحب للحرارةمحب للحرارة live in hot environments.live in hot environments.

The optimum temperatures for The optimum temperatures for most thermophiles are 60 - 80most thermophiles are 60 - 80°°C. C.

B)- bacteriaB)- bacteria

Bacteria is considered Bacteria is considered as the most known prokarotes.as the most known prokarotes.

The major bacterial taxa (species) are now accorded The major bacterial taxa (species) are now accorded kingdom status by most prokaryotic systematistskingdom status by most prokaryotic systematists علماء علماء.. التصنيفالتصنيف

Different types of diseases are caused by bacteria Different types of diseases are caused by bacteria includincludinging cholera, many sexually transmissible cholera, many sexually transmissible diseasesdiseasesاألمراض الجنسية المعديةاألمراض الجنسية المعدية , and certain types of food , and certain types of food poisoningpoisoningالتسمم الغذائيالتسمم الغذائي ..

However, more bacteria are beneficialHowever, more bacteria are beneficialمفيدةمفيدة ..Bacteria in our intestinesBacteria in our intestinesأمعائناأمعائنا produce important produce important

vitamins.vitamins.Bacteria recycle COBacteria recycle CO22 and other chemical elements and other chemical elements

between organic matter and the soil and between organic matter and the soil and atmosphere.atmosphere.

Bacteria often live in close association among Bacteria often live in close association among themselves and with eukaryotes in symbiotic themselves and with eukaryotes in symbiotic relationshipsrelationshipsعالقة تبادل منفعةعالقة تبادل منفعة ..

Harmful prokaryotes (Harmful prokaryotes (PathogenesPathogenesرضاتOمPرضاتالمOمPالم ))

Some pathogens produce disease by Some pathogens produce disease by invading the tissues of the host.invading the tissues of the host.

More commonly, pathogens cause More commonly, pathogens cause illness by producing poisons, called illness by producing poisons, called exotoxinsexotoxins السموم الخارجيةالسموم الخارجية and endotoxins and endotoxins السموم السموم

..الداخليةالداخلية

Pathogenic prokaryotes cause about half of all Pathogenic prokaryotes cause about half of all human disease. human disease.

The actinomycete that causes The actinomycete that causes tuberculosis is an example of this source tuberculosis is an example of this source of symptoms.of symptoms.

Beneficial prokaryotes (Beneficial prokaryotes (النافعةالنافعة))

Humans have learned to exploit the diverse Humans have learned to exploit the diverse metabolic capabilities of prokaryotes, for metabolic capabilities of prokaryotes, for scientific research and for practical purposes.scientific research and for practical purposes.

PProkaryotes are used to solve environmental rokaryotes are used to solve environmental problems.problems.

Humans also use bacteria as metabolic Humans also use bacteria as metabolic “factories” for commercial products“factories” for commercial productsالمنتجات التجاريةالمنتجات التجارية ..

The application of organisms to remove The application of organisms to remove pollutants from air, water, and soil is pollutants from air, water, and soil is bioremediationbioremediation يات أحيائيةSقT TقSيات أحيائيةمPن مPن