MAMALIA AIR

Water Mammal yaitu mamalia yang hidup di laut maupun di air tawar. Contoh hewan ini

adalah Sea Lions, The Walrus, Sperm Whale, Beluga Whale, Blue Whale, Manatees,

Narwhal, Platypus, Dolphins, Dugong, Elephant Seal, Northern Fur Seal, Gray seal, Leopard

Seal,Sea Otters.

Ciri-ciri mamalia

a. Mempunyai kelenjar susu yang terletak disisi bawah tubuh (di ketiak). Betina dapat

mengeluarkan susu setelah melahirkan. Kelenjar ini seperti kelenjar keringat, jadi

diatur oleh hormon. Air susu marine mammal mengandung 40-50% lemak untuk

mensupport pertumbuhan bayinta agar memiliki lapisan lemak yang cukup.

b. Melahirkan (viviparous), menyusui.

c. Bulu, sedikitnya ada dalam satu siklus hidup. Bulu ikan paus hanya beberapa helai di

sekitar tenggorokan dan hilang setelah dewasa. Bulu tumbuh dari kantong bulu di

dalam kulit yang dilengkapi dengan kelenjar palit yang mengeluarkan minyak sehingga

nampak mengkilat. Bulu berperan sebagai termoregulasi (pengatur suhu / memper -

tahankan suhu tubuh pada tingkat tertentu.

d. Jantung terdiri dari 4 bilik

e. Eritrocit tanpa inti dan bi concaf

f. Otak relatif besar

g. Pada rongga dada terdapat iga dan diaphragma.

h. Marine mammal bernafas dari udara sedangkan hewan laut bernafas dari udara yang

terlarut di air.

i. Suhu tubuh relatif lebih tinggi dari suhu lingkungannya, karena dibantu oleh lapisan

lemak dan bulu di tubuhnya.

j. Mempunyai kemampuan melawan arus (countercurrent exchange) seperti gerakan

hauling (menggulung) untuk mengurangi penurunan panas tubuh.

Marine Mammal/ Mamalia laut

Adalah mamalia yang hidup di laut atau mencari makannya di laut. Merupakan

evolusi dari nenek moyang nya yang hidup di daratan kemudian beradaptasi hidup di air.

Umumnya besar-besar (charismatic megafauna), bentuk tubuhnya hydrodynamis,

ekstremitas nya termodifikasi untuk bergerak di air dan mengalami adaptasi untuk berbagai

suhu (termoregulasi) karena beberapa species dapat beradaptasi untuk berbagai tingkat

suhu karena memiliki lapisan lemak yang tebal (tick layer blubber) untuk mencegah

hilangnya panas tubuh. Hewan laut yang beradaptasi penuh hidup di air adalah ordo

Cetacea dan Sirenia yang seluruh siklus hidupnya di dalam air. Sedangkan ordo lainnya

memanfaatkan sebagian waktunya di daratan. Beruang kutub sebagian besar hidupnya

dimanfaatkan di laut meskipun lautnya beku. sangat pandai berenang di laut terbuka dalam

satu hari dapat mencapai 74 km, sehingga beruang kutub oleh ilmuwan digolongkan dalam

marine mammal.

Beberapa jenis mamalia ini menuju kepunahan, bahkan banyak yang saat ini sudah

punah. karena dulunya di eksploitasi untuk diambil lemak, daging, taring dan bulunya.

Sehingga saat ini banyak dilindungi. Mamalia air tedapatasi untuk berenang memanfaatkan

sirip-nya untuk bergerak. Ikan juga berenang menggunakan sirip-2nya. Ikan umumnya

mempunyai sirip caudal yang tegak sedangkan marine mamalia mempunyai sirip caudal

yang horisontal.

Kelompok marine mamalia

Diperkirakan terdapat 120 species yang dikelompokkan menjadi 3 ordo.

1. Sirenia / sirenians : Famili Trichechidae : manatee (3 species)

Famili Dugongidae / dugong (1 species)

2. Cetacea (, dolphins dan Lumba-lumba / porpoises)

Sub ordo Mysticeti : Baleen whales/ Paus ( 14 atau 15 species)

Sub ordo Odontoceti : Toothed whales (± 73 species)

3. Carnivora

Super famili : Pinnipedia (berasal dari nenek moyang ber gigi taring)

Famili Phocidae : true seals / anjing laut (± 20 species)

Famili Otariidae : eared seals (± 16 species)

Famili Odobenidae : walrus (1 species)

Famili Mustelidae : sea otter (Enhydra lutris)

Marine otter (Lontra felina)

Famili Ursidae : Polar bear (beruang kutub) Ursus maritimus

Sea Lions

The Walrus

The Manatee

Platypus

The platypus lives in small streams and rivers over a large area of eastern Australia. The map above shows this with dark purple. It has been seen in alpine lakes in Tasmania in the south, and north in Queensland as far as the Cape York Peninsula in tropical rain forest rivers.[3]

In the past, platypuses lived in South Australia but they no longer live there. There are platypus on Kangaroo Island, but these were brought to the island in an attempt to save animals people thought might become extinct.[5] There are very few if any platypuses left in most the Murray-Darling Basin.[6] The water there is no good because people used it to grow plants, and cleared the trees from the land. It is strange that the platypus does not live in some healthy rivers. It does live in some less healthy coastal rivers, for example the Maribyrnong River in Victoria.

Platypus are difficult to see in the wild. They dislike areas with people, spend most of their time underground or under water, and sleep during the day. At Eungella National Park in Queensland, there are spots on the river with viewing areas where wild platypus can usually be seen each evening.[4]

Narwhal Platypus

Reproduksi nya bertelur The eggs develop in utero for about 28 days with only about 10 days of external incubation (in contrast to a chicken egg, which spends about 1 day in tract and 21 days externally).[34] After laying her eggs, the female curls around them. The incubation period is separated into three parts. In the first, the embryo has no functional organs and relies on the yolk sac for sustenance. The yolk is absorbed by the developing young.[44] During the second, the digits develop, and in the last, the egg tooth appears.[45]

The newly hatched young are vulnerable, blind, and hairless, and are fed by the mother's milk. Although possessing mammary glands, the Platypus lacks teats. Instead, milk is released through pores in the skin. There are grooves on her abdomen that form pools of milk, allowing the young to lap it up.[3][33] After they hatch, the offspring are suckled for three to four months. During incubation and weaning, the mother initially only leaves the burrow for short periods to forage. When doing so, she creates a number of thin soil plugs along the length of burrow possibly to protect the young from predators; pushing past these on her return forces water from her fur and allows the burrow to remain dry.[46] After about five weeks, the mother begins to spend more time away from her young and at around four months the young emerge from the burrow.[33] A platypus is born with teeth, but these drop out at a very early age, leaving the horny plates they grind their food with.[47]

The fossil is thought to be about 110 million years old, which means that the Platypus-like animal was alive during the Cretaceous period, making it the oldest mammal fossil found in Australia. Monotrematum sudamericanum, another fossil relative of the Platypus, has been found in Argentina, indicating that monotremes were present in the supercontinent of Gondwana when the continents of South America and Australia were joined via Antarctica (up to about 167 million years ago).[16][51]

DolphinFor other uses, see Dolphin (disambiguation)

.

Bottlenose Dolphinbreaching in the bow wave of a boat

Dolphins are marine mammals that are closely related to whales and porpoises. There are almost forty species of dolphin in seventeen genera. They vary in size from 1.2 m (4 ft) and 40 kg (90 lb) (Maui's Dolphin), up to 9.5 m (30 ft) and 10 tonnes (9.8 LT; 11 ST) (the Orca or Killer Whale). They are found worldwide, mostly in the shallower seas of the continental shelves, and are carnivores, mostly eating fish and squid. The family Delphinidae is the largest in the Cetacea, and relatively recent: dolphins evolved about ten million years ago, during the Miocene. Dolphins are considered to be amongst the most intelligent of animals and their often friendly appearance and seemingly playful attitude have made them popular in human culture.

Common Dolphin

Spotted Dolphin

Commerson's Dolphin

Dusky Dolphin

Killer Whales, a lso known as Orcas

Origin of the name

The name is originally from Ancient Greek δελφίς (delphís; "dolphin"), which was related to the Greek δελφύς (delphys; "womb"). The animal's name can therefore be interpreted as meaning "a 'fish' with a womb".[1] The name was transmitted via the Latin delphinus, Middle Latin dolfinus and the Old French daulphin, which reintroduced the ph into the word.

The word is used in a few different ways. It can mean:

Any member of the family Delphinidae (oceanic dolphins), Any member of the families Delphinidae and Platanistoidea (oceanic and river

dolphins), Any member of the suborder Odontoceti (toothed whales; these include the

above families and some others),

Used casually as a synonym for Bottlenose Dolphin, the most common and familiar species of dolphin.

In this article, the second definition is used. Porpoises (suborder Odontoceti, family Phocoenidae) are thus not dolphins in this sense. Orcas and some closely related species belong to the Delphinidae family and therefore qualify as dolphins, even though they are called whales in common language. A group of dolphins can be called a "school" or a "pod". Male dolphins are called "bulls", females "cows" and young dolphins are called "calves".[2]

The Boto, or Amazon River Dolphin Suborder Odontoceti, toothed whales

o Family Delphinidae, oceanic dolphins Genus Delphinus

Long-Beaked Common Dolphin , Delphinus capensis Short-Beaked Common Dolphin , Delphinus delphis

Genus Tursiops Common Bottlenose Dolphin , Tursiops truncatus Indo-Pacific Bottlenose Dolphin , Tursiops aduncus

Genus Lissodelphis Northern Rightwhale Dolphin , Lissodelphis borealis Southern Rightwhale Dolphin , Lissiodelphis peronii

Genus Sotalia Tucuxi , Sotalia fluviatilis Costero , Sotalia guianensis

Genus Sousa Indo-Pacific Hump-backed Dolphin , Sousa chinensis

Chinese White Dolphin (the Chinese variant), Sousa chinensis chinensis

Atlantic Humpbacked Dolphin , Sousa teuszii Genus Stenella

Atlantic Spotted Dolphin , Stenella frontalis Clymene Dolphin , Stenella clymene Pantropical Spotted Dolphin , Stenella attenuata Spinner Dolphin , Stenella longirostris Striped Dolphin , Stenella coeruleoalba

Genus Steno Rough-Toothed Dolphin , Steno bredanensis

Genus Cephalorynchus Chilean Dolphin , Cephalorhynchus eutropia Commerson's Dolphin , Cephalorhynchus commersonii Heaviside's Dolphin , Cephalorhynchus heavisidii Hector's Dolphin , Cephalorhynchus hectori

Genus Grampus Risso's Dolphin , Grampus griseus

Genus Lagenodelphis Fraser's Dolphin , Lagenodelphis hosei

Genus Lagenorhyncus Atlantic White-Sided Dolphin , Lagenorhynchus acutus Dusky Dolphin , Lagenorhynchus obscurus Hourglass Dolphin , Lagenorhynchus cruciger Pacific White-Sided Dolphin , Lagenorhynchus obliquidens Peale's Dolphin , Lagenorhynchus australis White-Beaked Dolphin , Lagenorhynchus albirostris

Genus Orcaella Australian Snubfin Dolphin , Orcaella heinsohni Irrawaddy Dolphin , Orcaella brevirostris

Genus Peponocephala Melon-headed Whale , Peponocephala electra

Genus Orcinus Killer Whale (Orca), Orcinus orca

Genus Feresa Pygmy Killer Whale , Feresa attenuata

Genus Pseudorca False Killer Whale , Pseudorca crassidens

Genus Globicephala Long-finned Pilot Whale , Globicephala melas Short-finned Pilot Whale , Globicephala macrorhynchus

Genus †Australodelphis †Australodelphis mirus

o Superfamily Platanistoidea Family Platanistidae

Ganges and Indus River Dolphin , Platanista gangetica with two subspecies

Ganges River Dolphin (or Susu), Platanista gangetica gangetica

Indus River Dolphin (or Bhulan), Platanista gangetica minor

Family Iniidae Amazon River Dolphin (or Boto), Inia geoffrensis

Family Lipotidae Chinese River Dolphin (or Baiji), Lipotes vexillifer

(possibly extinct, since December 2006) Family Pontoporiidae

La Plata Dolphin (or Franciscana), Pontoporia blainvillei

Six species in the family Delphinidae are commonly called "whales" but are strictly speaking dolphins. They are sometimes called blackfish.

Melon-headed Whale , Peponocephala electra Killer Whale (Orca), Orcinus orca Pygmy Killer Whale , Feresa attenuata

Wolphin Kawili'Kai at the Sea Life Park in Hawaii.

False Killer Whale , Psudorca crassidens Long-finned Pilot Whale , Globicephala melas Short-finned Pilot Whale , Globicephala

macrorhynchus

Hybrid dolphins

In 1933, three strange dolphins were beached off the Irish coast; these appeared to be hybrids between Risso's Dolphin and the Bottlenose Dolphin.[3] This mating has since been repeated in captivity and a hybrid calf was born. In captivity, a Bottlenose Dolphin and a Rough-toothed Dolphin produced hybrid offspring.[4] A Common-Bottlenose hybrid lives at SeaWorld California [5] Various other dolphin hybrids live in captivity around the world or have been reported in the wild, such as a Bottlenose-Atlantic Spotted hybrid.[6] The best known hybrid however is the Wolphin, a False Killer Whale-Bottlenose Dolphin hybrid. The Wolphin is a fertile hybrid, and two such Wolphins currently live at the Sea Life Park in Hawaii, the first having been born in 1985 from a male False Killer Whale and a female Bottlenose. Wolphins have also been observed in the wild.[7]

Dugong

Not to be confused with Dewgong or DougongDugong

Fossil range: Early Eocene–Recent

Conservation status Binomial name

Vulnerable (IUCN 3.1)[2]

Dugong dugon (Müller, 1776)

Scientific classification Natural range of D. dugon.

Kingdom: Animalia Subfamily: DugonginaeSimpson, 1932

Phylum: Chordata

Class: Mammalia Genus: DugongLacépède, 1799

Order: Sirenia Species: D. dugon

Family: DugongidaeGray, 1821

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