ChondrichthyseChondrichthyse

Alex Gosse and Zac DoucetteAlex Gosse and Zac Doucette

Phylogenetic TreePhylogenetic Tree

Taxonomists:Taxonomists:Characteristics for Animalia Characteristics for Animalia

• HeterotrophsHeterotrophs

• Multicellular Multicellular

• usually eukaryoticusually eukaryotic

• motile at some point in lifemotile at some point in life

• lack cell wallslack cell walls

• reproduce sexuallyreproduce sexually

Characteristics ChordataCharacteristics Chordata• skeletal rod called Notochord, lying on the skeletal rod called Notochord, lying on the

dorsal side of the bodydorsal side of the body

• nerve cord that lies dorsally in the bodynerve cord that lies dorsally in the body

• Pharyngeal Gill slits Pharyngeal Gill slits

• Digestive system, circulatory system, and Digestive system, circulatory system, and nervous system are all well developednervous system are all well developed

• post-anal tailpost-anal tail

• closed circulationclosed circulation

• they reproduce sexuallythey reproduce sexually

Characteristics for Characteristics for ChondrichthyseChondrichthyse

• poikilothermic (cold blooded)poikilothermic (cold blooded)

• swim bladder and lungs are absentswim bladder and lungs are absent

• digestive systems have intestinal digestive systems have intestinal spiral valves (exception of spiral valves (exception of Holocephali)Holocephali)

• have a cloacahave a cloaca

• do not have bone marrowdo not have bone marrow

• red blood cells are produced in the spleen red blood cells are produced in the spleen and special tissue around the gonadsand special tissue around the gonads

• tough skin is covered with dermal teeth tough skin is covered with dermal teeth (exception Holocephali, as the teeth are (exception Holocephali, as the teeth are lost in adults)lost in adults)

• water dwelling vertebrates with gills water dwelling vertebrates with gills throughout life throughout life

• limbs in the form of finslimbs in the form of fins

Hammerhead Shark

Great White Shark

Sting RayBonnet head Shark

Spotted Eagle Ray

Tiger Shark

Taxon Spotted Eagle Ray

Great White Shark

Bonnethead Shark

Kingdom Anamilia Anamillia Anamillia

Phylum Chordata Chordata Chordata

Class Chondrichthyes Chondrichthyes Chondrichthyes

Order Myliobatiformes Lamniformes Carcharhiniformes

Family Myliobatidae Lamnidae Sphyrnidae

Genus Aetobatus Carcharodon Sphyrna

Species A. Narinari C. Carcharias S. Tiburo

Life Cycle of The Great Life Cycle of The Great White SharkWhite Shark

• Delivery is in Spring or Summer.Delivery is in Spring or Summer.

• Reproductive cycle is ovoviviparous: Reproductive cycle is ovoviviparous: eggs are retained within the body of eggs are retained within the body of the female.the female.

• Pups hatch from egg capsules inside Pups hatch from egg capsules inside the mothers uterus and are born the mothers uterus and are born soon afterward. (live birth)soon afterward. (live birth)

• Litter sizes range from 2-17Litter sizes range from 2-17

• Leave mothers side as soon as born.Leave mothers side as soon as born.

• The pup's jaws develop in the first month The pup's jaws develop in the first month and the stronger ones eat their weaker and the stronger ones eat their weaker unborn siblings. unborn siblings.

• Females mature at 3.5-4.1 m in length Females mature at 3.5-4.1 m in length and 9-10 years of ageand 9-10 years of age

• Males mature at 4-5 m in length and 14-Males mature at 4-5 m in length and 14-16 years of age16 years of age

• After maturity they can reproduce (little After maturity they can reproduce (little is known about reproduction)is known about reproduction)

• Mothers give birth at same spot every Mothers give birth at same spot every yearyear

• Life span is 30 yearsLife span is 30 years

Anatomical Features of Anatomical Features of SharkShark

• Their skin is rough and harsh like sand Their skin is rough and harsh like sand paper. Their skin is made up of dermal paper. Their skin is made up of dermal denticles which are minuscule placoid scales denticles which are minuscule placoid scales that are similar to teeth. These dermal that are similar to teeth. These dermal denticles are even covered in enamel called denticles are even covered in enamel called vitro dentine, also including dentine and a vitro dentine, also including dentine and a pulp cavity; they are extremely comparable pulp cavity; they are extremely comparable to teeth.to teeth.

• Skeletons are made of cartilage rather than Skeletons are made of cartilage rather than bonebone

• Types of fins: pectoral, pelvic, dorsal, anal, Types of fins: pectoral, pelvic, dorsal, anal, caudalcaudal

• Gills to aid in respiration. Side of its head Gills to aid in respiration. Side of its head 5-7 gill slits ( in order for gas exchange to 5-7 gill slits ( in order for gas exchange to happen correctly there must be water happen correctly there must be water running over these gills at all times)running over these gills at all times)

• Shark spiracle (Slits located behind the Shark spiracle (Slits located behind the eye) send blood vessel immediately to the eye) send blood vessel immediately to the eyes and brain of the shark.eyes and brain of the shark.

•Sharks have a two chambered heart with an atrium and a ventricle. The heart is an S-shaped tube that is located in the head of the shark. The blood is pumped by the heart through the afferent bronchial arteries to capillaries in the gills. The blood goes through efferent bronchial arteries then to the tissues of the body and finally back to the heart in veins.

•Sharks swallow their food whole or bite it into very large pieces. They have U- shaped stomachs with acids and enzymes to dissolve what is eaten. The stomach produces a mush that enters the intestines. Only this mush can enter because of the pyloric valve is small. Indigestible things are vomited.

• Sharks get rid of body waste in two Sharks get rid of body waste in two ways. Some waste products, such as ways. Some waste products, such as carbon dioxide, are expelled through carbon dioxide, are expelled through the gills. Other body waste is the gills. Other body waste is excreted through the digestive tract. excreted through the digestive tract.

•Sharks extract oxygen from seawater as it passes over its gills. Unlike other fish, sharks gills lie in a row behind the head, and are not covered. Just behind the eye there is a modified slit called a spiracle. This slit helps the shark with taking in water during respiration. When the shark is moving, water passes through the mouth and over the gills, this process is called ‘ram ventilation’.

• The word Chondrichthyse includes The word Chondrichthyse includes the latin word for cartilage which is a the latin word for cartilage which is a major feature for that taxon.major feature for that taxon.

• Sharks have inner ears but no outer Sharks have inner ears but no outer ears.ears.

• Sharks have been around for over Sharks have been around for over 300 million years.300 million years.

SourcesSources

• http://www.fossilmuseum.net/Tree_of_Life/PhylumChordata/ClassChondrichthyes.htm

• http://www.the-shark-side-of-life.com/shark-anatomy.html

• http://animaldiversity.ummz.umich.edu/accounts/http://animaldiversity.ummz.umich.edu/accounts/Chondrichthyes/classification/Chondrichthyes/classification/

• http://www.ucmp.berkeley.edu/vertebrates/basalfish/http://www.ucmp.berkeley.edu/vertebrates/basalfish/chondrintro.htmlchondrintro.html

• http://animals.about.com/od/cartilaginousfishes/p/http://animals.about.com/od/cartilaginousfishes/p/cartilaginousfishes.htmcartilaginousfishes.htm

• http://www.fao.org/docrep/006/Y5261E/y5261e08.htmhttp://www.fao.org/docrep/006/Y5261E/y5261e08.htm

• http://marinebio.org/species.asp?id=38http://marinebio.org/species.asp?id=38

• http://sharks101.wordpress.com/circulatory-and-respiratory-http://sharks101.wordpress.com/circulatory-and-respiratory-system/system/

• http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2140763/http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2140763/