1. CETACEANS
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2. There are currently 81 recognized species of Cetaceans
There are currently 81 recognized species of Cetaceans. This is the largest group of Marine Mammals, consisting of Dolphins, Porpoises, and Whales.
These, of all the Marine Mammals, have made the most complete transition to aquatic life and spend their entire lives in the water.

3. CHARACTERISTICS:
They breath air through lungs and have a nostril (blowhole ) (single, or double) positioned on top of their skulls
Horizontal caudal fin
Rudimental posterior limbs
Very few hairs
They are streamlined, and remarkably fish-like.

4. TWO SUBORDERS OF ORDER CETACEA
Suborder Odontoceti (toothed whales)
They have teeth
They echolocate (send sounds through water, and receive echo)
Includes killer whale, sperm whale, dolphins, porpoises, and many others
Suborder Mysticeti (baleen whales)
Have not teeth but rows of baleen plates hanging from the mouth ceiling
Includes blue whale, finback whale, humpback whale, gray whale

5. Differences between dolphins and porpoises
Dolphins have:
An elongated snout (not correctly, a rostrum)
A falcate dorsal fin
Conical-shaped teeth
Killer whale jawbone

6. Differences between dolphins and porpoises
Porpoises have:
A blunt snout (not correctly, a rostrum)
A triangle-shaped dorsal fin
Spade-shaped teeth

7. Echolocation
The melon is an ovoid shaped fatty organ found in the forehead of all toothed whales and believed to be used in echolocation.
The dolphin is able to generate sound in the form of clicks, within nasal sacs, situated behind the melon. When the sound strikes an object, some of the soundwave energy is reflected back.

8. Mysticeti: The baleen whales
Mysticeti whales have baleen and not teeth
Baleen plates:
Hang as parallel rows from the upper jaw
Are made of keratin
Are used as a strainer to capture zooplankton, krill and small fish

9. Baleen plates

10. The Mediterranean Sea
Dolphin frescoes from Queen’s Megaron in Knossos (Crete, Greece)

12. Regular species in the Mediterranean Sea (8)
Common dolphin Delphinus delphis
Bottle-nosed dolphin Tursiops truncatus
Stenella striata Stenella coeruleoalba
Long-finned pilot whale Globicephala melas
Risso’s dolphin Grampus griseus
Sperm whale Physeter macrocephalus
Cuvier’s beacked whale Ziphius cavirostris
Fin whale Balaenoptera physalus

13. Delphinus delphis Linnaeus, 1758
COMMON DOLPHIN
Suborder: Odontoceti
Family: Delphinidae
DELFINO COMUNE
Identification Typical hourglass pattern on each side created by overlapping of the contrasting dorsal and ventral patches to form a "V"-shaped saddle below the dorsal fin. Maximum lenght about 2 m.
Distribution
One of the most widely distributed cetaceans in temperate, tropical and sub-tropical seas. It was widespread and abundant in the Mediterranean Sea until the late 1960s. The populations declined dramatically over the past years.
Ecology
Adaptable to different habitats. It is a pelagic, offshore dolphin, also frequent in the coastal zones. It feeds mainly on small epipelagic fishes, and cephalopods.

14. Tursiops truncatus (Montagu, 1821)
BOTTLENOSE DOLPHIN
Suborder: Odontoceti
Family: Delphinidae
TURSIOPE
Identification A well-defined beak (snout, rostrum) that is sharply demarcated from the forehead by a distinct crest. from dark grey through to light grey to brown. Maximum length about 3 m.
Distribution
Temperate and tropical waters of the Atlantic, Pacific and Indian Oceans as well as the Mediterranean, Black and Red Seas. The commonest cetacean over the Mediterranean Sea continental shelf. The most representative species of the Adriatic Sea.
Ecology
Coastal zones (sometimes in estuaries) and pelagic waters. It is believed that there are two forms of this species, a coastal form (smaller size) and a pelagic form. Mainly ichthyophagous, but when necessary feeds on cephalopods and crustaceans.

15. Stenella coeruleoalba (Meyen, 1833)
STRIPED DOLPHIN
Suborder: Odontoceti
Family: Delphinidae
STENELLA STRIATA
Identification Striped dolphin with a long dark beak. A lateral stripe and spinal blaze are characteristic and distinguish the striped dolphin from other white-bellied oceanic dolphins. Maximum lenght about 3 m.
Distribution
Widely distributed in temperate and tropical waters of the world. Currently the most abundant species of Delphinidae in the Mediterranean (except the E part) and in Italian waters.
Ecology
Inhabits preferentially the waters off the continental shelf. This dolphin has a very varied and adaptable diet. In the Mediterranean, it feeds on cephalopods, fishes and crustaceans.

16. Globicephala melas (Traill, 1809)
LONG-FINNED PILOT WHALE
Suborder: Odontoceti
Family: Delphinidae
GLOBICEFALO
Identification Long-finned pilot whale has bulbous forehead and a short, imperceptible, beak. Adults black in colour, new-born and immatures are lighter in color. Most adults have scars, from squid sucker or from teeth of conspecifics. Maximum length about 5-6 m.
Distribution
In medium-temperate waters of the N Atlantic and in the sub-polar oceans. Common in the W Med. Doubtful in the E Med. Absent from the Black Sea.
Ecology
Pelagic species inhabiting offshore habitats of the deepest portion of the continental slope. It feeds mainly on cephalopods, it also catches pelagic fishes.

17. Grampus griseus (Cuvier, 1812)
RISSO’S DOLPHIN
Suborder: Odontoceti
Family: Delphinidae
GRAMPO
Identification
A large dolphin with a robust body that
becomes slender behind the dorsal fin.
Bulbous head, with no beak. At birth it
has a uniform light colour, but adults are typically
silver-grey and the body is covered with scratches and scars. Maximum length about 4 m.
Distribution
A cosmopolitan species, absent only in seas of high latitudes. Common in the Med. but the presence in the Levant basin is unknown. Absent from the Black Sea.
Ecology
A warm water and deep pelagic species preferring continental slopes and submarine canyons. It feeds on crustaceans and cephalopods (it prefers squids). Squid bites may be the cause of at least some of the scars on its skin.

18. Physeter macrocephalus Linnaeus, 1758
SPERM WHALE
Suborder: Odontoceti
Family: Physeteridae
CAPODOGLIO
Identification Has a huge head which
is 1/3 to 1/4 of the total
body length. The spermaceti organ in the head contains oil-like wax for which the sperm whale was highly valued and relentlessly hunted. Coloration is dark grey to brown
Maximum length about 18 m.
Distribution
Widely distributed in offshore waters from the tropics to the polar regions. In Italian waters, it seems to be more frequent in the Pelagos Sanctuary.
Habitat
It is a typical cetacean of deep pelagic waters, being able to dive more than 2,500 m. It prefers the continental slope. It feeds primarily upon large mesopelagic squids, but also various fish and sharks.
Skin scars
Marguerite formation

19. Ziphius cavirostris Cuvier, 1823
CUVIER’S BEACKED WHALE
Suborder: Odontoceti
Family: Ziphiidae
ZIFIO
Identification
A stout body and small
sloping head with a
short beak and curved mouth.
The colour tends to be light to dark rusty brown or even grey, although the head and upper thorax of older animals are lighter in both sexes. Maximum length about 9 m.
Distribution
Has a very broad distribution in all oceans, in temperate and tropical waters, but the detailed range is poorly known. In Italian waters, it seems to be more frequent in the Ligurian and Tyrrhenian Seas.
Ecology
Typical pelagic cetacean, it is rarely observed near the coast or continental shelf. It feeds mainly on Cephalopoda, as well as deep-sea fishes, since it is capable of remarkable dives.

20. Balenoptera physalus (Linnaeus, 1758)
FIN WHALE
Suborder: Mysticeti
Family: Balenopteridaedae
BALENOTTERA COMUNE
Identification
The fin whale is streamlined, rounded in the
front, compressed in the tail region with a distinct
ridge along the back behind the dorsal fin. Coloration is dark
grey to brownish black dorsally, grading to pale or white ventrally. The undersides of the flippers and flukes are white. The head is mostly dark, but the lower jaw is white. Maximum length about 24 m.
Distribution
The fin whale is present in all temperate and cold waters. In the Med. sea it is more frequent in the
W sector. In Italian waters this species is frequently observed in summer in the W Ligurian Sea.
Habitat
It is generally found in waters beyond the continental shelf. However, it can also move into coastal waters to feed on krill, fish and cephalopods, although diet varies.

21. Irregular species in the Mediterranean Sea
North Atlantic right whale Eubalaena glacialis
Minke whale Balaenoptera acutorostrata
Sei whale Balaenoptera borealis
Umpback whale Megaptera novaeangliae
Dwarf sperm whale Kogia sima
Northern bottlenose whale Hyperoodon ampullatus
Blainville’s beaked whale Mesoplodon densirostris
Sowerby’s beaked whale Mesoplodon bidens
Killer whale Orcinus orca
False killer whale Pseudorca crassidens
Indo-Pacific umpbacked dolphin Sousa chinensis
Rough-toothed dolphin Steno bredanensis
Harbour porpoise Phocoena phocoena

22. The International Sanctuary for Mediterranean Marine Mammals
A large Marine Protected Area ( km2) (waters of France, Italy, and Monaco), including shallow coastal, and deep pelagic habitats.

23. Why are cetaceans so abundant?
presence in the area of a permanent frontal system,
and consequent upwelling of deep, nutrient-rich waters.

24. nutrients at the surface sustains primary production in the area, in striking contrast with most of the Mediterranean pelagic domain

25. The main Mediterranean euphausiid:
Meganyctiphanes norvegica

26. Threats Fishing and fishers Pollution hydrocarbons toxic chemicals
noise
Collisions
Disturbance
Global change

27. Archaeoceti: The Marine Atavism of Early Whales; The Anachronistic Return of Tetrapods to Oceans
Trevor Fanning

28. Paleontology strengthens the theory of evolution through well-defined lineages such as the early whales.

29. Whales evolved from dog-sized land mammals beginning ~ 52. 5 Ma
Whales evolved from dog-sized land mammals beginning ~ 52.5 Ma. Pakicetus, one of the oldest known cetacean’s ancestors, had a long-snouted skull with primitive carnivorous teeth lining its jaws
Pakicetus inachus, a cetacean ancestor from the Early Eocene of Pakistan. Nummelai et al., (2006).

30. Pakicetus's bones reveal it was semi-aquatic.
Dense cortical limb bones, instead of spongy bones, reduces buoyancy in the water.
Extant Hippopotamuses have the same bone structure as the cetacean ancestors

31. Indohyus was an even-toed herbivore related to early cetaceans.
Indohyus major, an artiodactyl described as an early ancestor of cetaceans, from the Middle Eocene of Kashmir, Thewissen (2007)

32. Hippos and Indohyus form sister clades to Cetacea.

33. Whales' nostrils migrated from nose to blowhole in the skull.

34. Vestigial hind limbs in whales no longer protrude from the body.

35. Cetacean hind-limbs are perceptible in embryos.
Dorudon
Basilosaurus

37. In 2001, the first archaeocete astragalus was found.

38. The double-pulley astragalus is a synapomorphy present in Cetacea and Artiodactyla.

39. -this water body was a nursery for the budding archaeocete lineage.
- The Sulaiman Mountain Range (Pakistan) was once the ocean floor of the Tethys Ocean.
-this water body was a nursery for the budding archaeocete lineage.
closure of Tethys
Opening of Indian Ocean
Late Eocene (about 37 My)

40. Wadi Al-Hitan, Egypt (Arabic for “Valley of the Whales”)

41. Fayoum, western desert of Egypt, was submerged during the Eocene.

42. Ambulocetids (48 My ago) were partially terrestrial, partially aquatic
Ambulocetus natans
Ambulo, -are, -avi, -atum: to walk
Natans, -antis: swimming, marine
i.e., genus named for its retained capacity to walk on land.

43. Remingtonocetidae 45 My ago
Named after Remington Kellogg ( ), the authority of his day on fossil whales.
Pictured (bottom) is the remingtonocetid type-specimen Kutchicetus.
Remingtonocetid was small, roughly the size of a river otter! (Bird for scale).

44. Basilosaurus (40 My ago) was the first fossilized Archaeocete to be discovered by humans (1830s).
A misnomer
the -saurus suffix implies this cetacean was a reptilian (lizard) like the much longer-extinct plesio-saurs!

45. Basilosaurus was the largest creature of its time, marine or terrestrial.

46. Basilosaurus contrasted with the primordial Ambulocetus skeletons.
The long-bodied archaeocete with negligible hind legs, was a basilosaurid, evolving much later than the early Ambulocetus.

47. MAUS collection:
60 cetaceans, 12 classified,
from My (Miocene)
3 holotypes
Messapicetus longirostris
Zygophyseter varolai
Archaescrictius ruggieroi

48. Pisa
(the Calci Certosa)
Natural History Museum
the cetacean gallery (19 scheletons of 53)