15
bare 1–4 live young, requiem sharks are ovoviviparous (10–80 pups per litter)
and viviparous (1–135 pups per litter) and hammerhead sharks are viviparous
(30–55 pups per litter).
6. Lamniformes (Mackerel sharks) date from the Jurassic Period (160–200 mya),
and consist of 15 species in 7 families: thresher sharks ( Alopiidae ), Cetorhinidae ,
Lamnidae , Megachasmidae , Mitsukurinidae , Odontaspididae , P seudocarchariidae
(no common names exist for the latter 6 families). These species are predominantly large active pelagic sharks with cylindrical/torpedo shaped bodies with 5
gill slits, 2 dorsal fi ns and anal fi ns. They are found worldwide from the intertidal
zone to deeper water and the open ocean. Reproduction is ovoviviparous (2–25
pups per litter depending on species). In one species, the sandtiger shark
( Carcharias taurus ), cannibalism occurs as the dominant pup will consume the
other embryos.
7. Orectolobiformes (Carpet sharks) originate from the Jurassic period (160–200
mya). This order consists of 33 species in 7 families: collared carpetsharks
( Parascyllidae ), blind sharks ( Brachaeluridae) , wobbegongs ( Orectolobidae ),
longtail carpetsharks ( Hemiscyllidae ), nurse sharks ( Ginglymostomatidae ),
zebra shark ( Stegostomatidae ), whale shark ( Rhincodontidae ). They can be
found worldwide in warm temperate and tropical seas, from the intertidal zone
to deep water. With the exception of the whale shark ( Rhincodon typus ) all
are bottom dwelling, they have 5 gill slits, 2 dorsal fi ns and anal fi ns. They utilise
a variety of reproductive strategies including oviparity (6–8 egg cases), ovoviviparous (20–30 pups per litter), viviparous (up to 300 pups per litter) and oophagy
(litter size unknown).
8. Heterodontiformes (Bullhead sharks) date back to the Triassic period (200–260
mya). Comprised of 9 species they are bottom dwelling stout-bodied sharks,
with 2 spined dorsal fi ns and anal fi ns. Their habitat varies between species
and ranges from the intertidal zone to continental and insular shelves. They are
nocturnal, preferring to rest in rocky crevices and caves during daylight.
Reproduction is oviparous, laying very distinctive egg cases which are screw
shaped; the number of eggs laid is unknown.” (Smith 2013 : «Shark Evolution
and Classifi cation», published online: http://saltwaterlife.co.uk/ws/sharkiologist/
articles/shark-evolution-and-classifi cation/ )
Because of diversity and special properties of their skeletal structures like teeth,
denticles, fi ns, eggs capsules, cartilage as well as biomechanics of their skin and
body shape, sharks seem to be a veritable gold mine for material scientists as well
as experts in bionics and biomimetics (Fig. 1.4 )
Order Batoidea
Skates, stingrays, sawfi shes, and guitarfi sh are representatives of cartilaginous
batoid fi shes (Claeson 2011 ), which possess dorsoventrally compressed bodies
ranging in shape from circular to rhomboidal (Compagno 1977 ; Aschliman et al. 2012 ).
In addition to marine habitats, they inhabit freshwater niches on fi ve continents
1.2 Part I: Biomaterials of Vertebrate Origin. An Overview
bare 1–4 live young, requiem sharks are ovoviviparous (10–80 pups per litter)
and viviparous (1–135 pups per litter) and hammerhead sharks are viviparous
(30–55 pups per litter).
6. Lamniformes (Mackerel sharks) date from the Jurassic Period (160–200 mya),
and consist of 15 species in 7 families: thresher sharks ( Alopiidae ), Cetorhinidae ,
Lamnidae , Megachasmidae , Mitsukurinidae , Odontaspididae , P seudocarchariidae
(no common names exist for the latter 6 families). These species are predominantly large active pelagic sharks with cylindrical/torpedo shaped bodies with 5
gill slits, 2 dorsal fi ns and anal fi ns. They are found worldwide from the intertidal
zone to deeper water and the open ocean. Reproduction is ovoviviparous (2–25
pups per litter depending on species). In one species, the sandtiger shark
( Carcharias taurus ), cannibalism occurs as the dominant pup will consume the
other embryos.
7. Orectolobiformes (Carpet sharks) originate from the Jurassic period (160–200
mya). This order consists of 33 species in 7 families: collared carpetsharks
( Parascyllidae ), blind sharks ( Brachaeluridae) , wobbegongs ( Orectolobidae ),
longtail carpetsharks ( Hemiscyllidae ), nurse sharks ( Ginglymostomatidae ),
zebra shark ( Stegostomatidae ), whale shark ( Rhincodontidae ). They can be
found worldwide in warm temperate and tropical seas, from the intertidal zone
to deep water. With the exception of the whale shark ( Rhincodon typus ) all
are bottom dwelling, they have 5 gill slits, 2 dorsal fi ns and anal fi ns. They utilise
a variety of reproductive strategies including oviparity (6–8 egg cases), ovoviviparous (20–30 pups per litter), viviparous (up to 300 pups per litter) and oophagy
(litter size unknown).
8. Heterodontiformes (Bullhead sharks) date back to the Triassic period (200–260
mya). Comprised of 9 species they are bottom dwelling stout-bodied sharks,
with 2 spined dorsal fi ns and anal fi ns. Their habitat varies between species
and ranges from the intertidal zone to continental and insular shelves. They are
nocturnal, preferring to rest in rocky crevices and caves during daylight.
Reproduction is oviparous, laying very distinctive egg cases which are screw
shaped; the number of eggs laid is unknown.” (Smith 2013 : «Shark Evolution
and Classifi cation», published online: http://saltwaterlife.co.uk/ws/sharkiologist/
articles/shark-evolution-and-classifi cation/ )
Because of diversity and special properties of their skeletal structures like teeth,
denticles, fi ns, eggs capsules, cartilage as well as biomechanics of their skin and
body shape, sharks seem to be a veritable gold mine for material scientists as well
as experts in bionics and biomimetics (Fig. 1.4 )
Order Batoidea
Skates, stingrays, sawfi shes, and guitarfi sh are representatives of cartilaginous
batoid fi shes (Claeson 2011 ), which possess dorsoventrally compressed bodies
ranging in shape from circular to rhomboidal (Compagno 1977 ; Aschliman et al. 2012 ).
In addition to marine habitats, they inhabit freshwater niches on fi ve continents
1.2 Part I: Biomaterials of Vertebrate Origin. An Overview