Extremely large and strong, Whales have no natural threats. They may weigh up to one hundred and fifty to two hundred tons. Body length often exceeds one hundred feet. Physique is fusiform and streamlined, allowing it to swim freely. Vertebrae of neck are joined together, providing stability in movement. Heart is four chambered and body temperature is regulated like all warm blooded mammals, the thick layer of blubber underneath the skin acting as an insulator. It also serves as a reservoir of fat. Lungs are present instead of gills as in fish, meaning that Whales have to surface periodically to breathe, though they can stay submerged for long periods. The blowhole is used for this purpose, numbering in two in case of Baleen Whales and one for Toothed Whales. Dorsal fin is often present. Sometimes small hind quarters are also observed, possibly vestigial like the pelvic bone, propulsion being done mainly by the tail fins or fluke.

Classified as predators, Whales consume plankton as their primary food source, though larger fish are often taken. Tonnes of krill are consumed daily by the Blue Whale, the largest creature in history. Highly intelligent animals, Whales often live in groups called Pods. These pods contain greater number of individuals in case of Toothed Whales that often move and hunt together. Adult males are called Bulls, and females Cows. Annually Whales migrate from the polar regions during winter season, traveling thousands of miles in seas. Speed of movement is fastest in case of Killer Whale or Orca, reaching up to fifty kilometers per hour. During their aquatic activities, Whales display several moves including Breaching where they jump above the water surface, possibly to get rid of parasites, play or socialize. At times they may Skyhop, that is raise their head above water and look around. Then there is Lobtailing, when Whales stick their muscular tail out of water, move it around and strike it on the water surface, possibly to send a warning through this loud sound.

Whales reproduce slowly, taking on average an year to give birth to a single offspring with a gap of two to three years between births. Calves are born tail first to prevent them from drowning and begin to swim almost immediately. In case of Blue Whales, they weigh two tons at birth and gain two hundred pounds daily during the first year of their lives. Mother feeds them through squirting the breast milk into their mouth, in order to prevent wastage. Bond is very strong between the calf and mother, who protects and feeds it up to one year of age. Lifespan is between forty to hundred years normally, though specimens older than two hundred years have been recorded, making Whales the longest living of all Mammals. 

Extremely large and strong, Whales have no natural threats. They may weigh up to one hundred and fifty to two hundred tons. Body length often exceeds one hundred feet. Physique is fusiform and streamlined, allowing it to swim freely. Vertebrae of neck are joined together, providing stability in movement. Heart is four chambered and body temperature is regulated like all warm blooded mammals, the thick layer of blubber underneath the skin acting as an insulator. It also serves as a reservoir of fat. Lungs are present instead of gills as in fish, meaning that Whales have to surface periodically to breathe, though they can stay submerged for long periods. The blowhole is used for this purpose, numbering in two in case of Baleen Whales and one for Toothed Whales. Dorsal fin is often present. Sometimes small hind quarters are also observed, possibly vestigial like the pelvic bone, propulsion being done mainly by the tail fins or fluke.

Classified as predators, Whales consume plankton as their primary food source, though larger fish are often taken. Tonnes of krill are consumed daily by the Blue Whale, the largest creature in history. Highly intelligent animals, Whales often live in groups called Pods. These pods contain greater number of individuals in case of Toothed Whales that often move and hunt together. Adult males are called Bulls, and females Cows. Annually Whales migrate from the polar regions during winter season, traveling thousands of miles in seas. Speed of movement is fastest in case of Killer Whale or Orca, reaching up to fifty kilometers per hour. During their aquatic activities, Whales display several moves including Breaching where they jump above the water surface, possibly to get rid of parasites, play or socialize. At times they may Skyhop, that is raise their head above water and look around. Then there is Lobtailing, when Whales stick their muscular tail out of water, move it around and strike it on the water surface, possibly to send a warning through this loud sound.

Whales reproduce slowly, taking on average an year to give birth to a single offspring with a gap of two to three years between births. Calves are born tail first to prevent them from drowning and begin to swim almost immediately. In case of Blue Whales, they weigh two tons at birth and gain two hundred pounds daily during the first year of their lives. Mother feeds them through squirting the breast milk into their mouth, in order to prevent wastage. Bond is very strong between the calf and mother, who protects and feeds it up to one year of age. Lifespan is between forty to hundred years normally, though specimens older than two hundred years have been recorded, making Whales the longest living of all Mammals. 

Generally speaking big cats are 1) Wild and 2) Considerably bigger than the small domestic or wild cats (a Siberian tiger for instance may be up to 100 times heavier than our 8 pound domestic feline). Other commonly used classifying method is the ability to roar. Big cats have an elongated larynx and elastic hyoid bone that enables them to roar (and prevents them from purring). Small cats are the opposite. Their hyoid bone is ossified, thus they are unable to roar, and may only purr.

Other interesting difference is the shape of pupils. All big cats have round pupils and small cats, apart from lynx, have slit-like pupils (exaggerated in bright light). Also big cats usually consume their meals lying down, apart from snow leopard, whereas cats - as we all know- eat in a sitting position! Many of the earlier classifications used to include only four species: Tiger, Lion, Jaguar and Leopard into big cats. However, today big cats are expanded to include also Cougar, Snow Leopard, Clouded Leopard and Cheetah.

Despite significant differences in size in all the big and small cats, all felines are remarkably similar in their basic body make-up and sensory perceptions. They have similar attributes and hunting and behavior profiles in most cases. They are in short a true representation of Nature's masterwork in creation. With grace and elegance, big cats are master predators and hunters!