Cetaceans

"Cetacean" is the word for all mammals, which includes whales, dolphins and porpoises.
The term cetacean comes from the Greek ketos, meaning "sea monster” an from the Latin cetus meaning "a large sea animal,"
Cetaceans are mammals who are adapted to life in the water.
Over 80 species of whales, dolphins and porpoises on Earth, from the small Hector's dolphin (39” long) to the huge blue whale (100 ft long)
Cetaceans are further divided into two groups: baleen whales and toothed whales.
Pronunciation: "Suh-tay-shun"

Evolution of whales
Cetaceans are thought to have evolved from hooved land mammals that lived about 50 million years ago.

http://www.robins-island.org/dolphins_evolution.php

Types of Cetaceans: according to how they feed

Mysticetes (baleen whales)

• include species such as the blue whale, fin whale, right whale and humpback whale.
  
• have hundreds of comb-like plates of baleen hanging from their upper jaw.
• feed by gulping large amounts of water containing hundreds or thousands of fish or plankton, then forcing the water out in between the baleen plates, leaving the prey inside to be swallowed whole
• 14 baleen whale species

Odontocetes (toothed whales)

• include the sperm whale, orca (killer whale), beluga and all of the dolphins and porpoises.
• these animals have cone-shaped or spade-shaped teeth
• usually capture one animal at a time and swallow it whole.
• feed mostly on fish and squid, although some orcas prey on other marine mammals.
• 72 different species

Cetacean Characteristics

• Are mammals, which means they are endothermic (commonly called warm-blooded)
• Their internal body temperature is about the same as a human's.
• They give birth to live young and breathe air through lungs just like we do. They even have hair.
• Unlike fish, which swim by moving their heads from side-to-side to swing their tail, cetaceans propel themselves by moving their tail in a smooth, up-and-down motion.
• Some cetaceans, such as the Dall's porpoise and the orca (killer whale) can swim faster than 30 miles per hour.

Breathing & Insulation

• When a cetacean wants to breathe, it has to rise to the water surface and exhale and inhale out of the blowholes located on top of its head.
• When the cetacean comes to the surface and exhales, you can sometimes see the spout, or blow, which is the result of the warm air in the whale's lungs condensing upon reaching the cool air outside.
• Whales do not have a coat of fur to keep warm, so they have a thick layer of fat and connective tissue called blubber underneath their skin.
• This blubber layer can be as much as 24 inches thick in some whales.

Senses & Diving

• Whales have a poor sense of smell, and depending on where they are, they may not be able to see well underwater.
• They have excellent hearing. They do not have external ears, but have tiny ear openings behind each eye. They can also tell the direction of sound underwater.
• Whales have collapsible rib cages and flexible skeletons, which allows them to compensate for high water pressure when they dive.
• They can also tolerate higher levels of carbon dioxide in their blood, allowing them to stay underwater for up to 1 to 2 hours for large whales.

Difference Between Dolphins & Porpoises:

Dolphins

• Dolphins have cone-shaped teeth
• Dolphins usually have a pronounced “beak,”
• Dolphins generally have a very curved or hooked dorsal fin
• Dolphins are larger than porpoises

Porpoises

• Porpoises have flat or spade-shaped teeth
• Porpoises do not have a beak.
• Porpoises have a triangular dorsal fin.
• Porpoises are generally smaller than dolphins.

Do Whales Sleep?

Whales are voluntary breathers, meaning they think about every breath they take.
A whale breathes through the blowholes on top of its head, so it needs to come up to the water surface to breathe. That means the whale needs to be awake to breathe.

How's a whale going to get any rest?

Unlike us, whales "sleep" by resting one half of their brain at a time.

While one half of the brain stays awake to make sure the whale breathes and alerts the whale to any danger in its environment, the other half of the brain sleeps.
We humans are involuntary breathers, meaning we breathe without thinking about it and have a "breathing reflex" that kicks into gear when we're sleeping or are knocked unconscious.
Whales do not appear to have REM (rapid eye movement) sleep that is characteristic of humans. This is the stage in which most of our dreaming occurs.

Where do cetaceans sleep?

Captive dolphins have been known to rest at the bottom of their pool for a few minutes at a time.

Large baleen whales such as humpbacks resting at the surface for sometimes half an hour at a time. These whales take slow breaths that are less frequent than a whale that's active. They are so relatively motionless on the surface that we refer to this behavior as "logging," because they look like giant logs floating on the water.

Do Whales Have Hair?

Whales are mammals, and one of the characteristics common to all mammals is the presence of hair. There are over 80 species of whales, and hair is only visible in some. Some of the larger baleen whales have visible hair. Eg.

• Humpback whale, which has golf ball-sized bumps on its head. Within each of these bumps, called tubercles, there is a hair follicle.
• Right whale, which has hairs on its chin and upper jaw,
• Bowhead whale, which has hairs on its lips, chin, snout and behind its blowhole.
• Baleen whales also have hairlike structures in their mouth called baleen, which is made of keratin, a substance found in hair and nails.

How do whales and dolphins swim?

Cetaceans use their tail to swim. Unlike fish, the tail of whales, dolphins and porpoises lies in an horizontal plane and it is moved up and down rather than from side to side. Muscles actively work when the tail is raised, while they rest (or almost completely rest) when the tail is lowered.

How do whales and dolphins communicate?

Cetaceans communicate mainly by producing a wide range of sounds, such as clicks, moans, creaks, squeaks, etc. Unlike mysticetes (baleen whales), most odontocetes (toothed cetaceans) also produce whistles, and their clicks plays a central role in a mechanism known as echolocation - an extremely powerful bio-sonar that allow them to detect other members of their group, prey, predators and also investigate the physical features of the aquatic environment.
Mysticeti (baleen whales) do not seem to use echolocation.

Whale Fun Facts

• Sperm Whales have the largest brain on the planet. It may weigh 20lbs.
• Fin whale is one of the fastest whales. They can swim over 20 miles per hour for short periods.
• Blue whale is the largest whale. They may grow up to 100 feet and weigh as much as several elephants.
• Harbor porpoise is one of the smallest whales. They grow to only about 5 feet in length.
• Killer whales are the largest dolphins. They get their name because they sometimes eat other, larger whales.
• A humpback whale may eat up to a ton of food every day.
• Whales can't breathe through their mouths. The mouth is connected directly to the stomach. They breathe through their blow holes, which go to the lungs.
• Sperm whale can hold its breath for at least an hour.
• The voice of the blue whale is one of the deepest voices on the planet. It is so powerful that it can travel for perhaps a 100 miles underwater.
• Blubber on a whale which lives in very cold water may reach up to 20” thick.
• Whales do not spout water. They are letting out air from their lungs.
• A new born baby blue whale may weigh two tons and be 25 feet long.
• Some whales do not have teeth. They have baleen. The largest baleen is that of the bowhead whale, whose baleen may be up to 10 ft long.
• There is a toothed whale which only has two teeth.
• Narwhales have one tooth hidden under the gums, but in the males the other tooth sticks out from their head like a tusk, which may grow to be 8 feet long.

Australia

Facts

In land area, Australia is the sixth largest nation after Russia, Canada, China, USA and Brazil.

It has, however, a relatively small population.

only nation to govern an entire continent and its outlying islands.

• The mainland is the largest island and the world’s smallest, flattest continent.
• Australia is called the land down under because it is below the equator.
• Australia is made up of 6 states and 2 territories.
• 18.3 million people live there.
• Canberra is the capital of Australia.
• The weather in Australia is warm and pleasant.
• Apart from Antarctica, Australia is the driest continent.
• Coastline stretches almost 50,000 kilometres & is linked by over 10,000 beaches
• More than 85% of Australians live within 50 kilometres of the coast
• The middle part of the country is called the outback.
• There are about 10 times more sheep than people in Australia. Sheep are raised for wool and for meat.
• A ranch is known as a station. Stations are very big.
• The first people to live in Australia were aborigines. Aboriginal means first.
• Most famous animals are marsupials, a mammal that has a pouch to carry its young.
  

Australian Flag
In 1901, the Commonwealth of Australia was formed.

Until this time, Australia used Britain's flag.

A competition was held to find the design for Australia's own flag.

Five designers shared the prize because they came up with similar ideas for the Australian flag.

The Aboriginal Flag
The Aboriginal Flag was designed by Harold Thomas, an artist and an Aboriginal, in 1971.
The black represents the Aboriginal people, the red the earth and their spiritual relationship to the land, and the yellow the sun, the giver of life.

Australia's National Anthem:
Advance Australia Fair

Fun Facts

The Sydney Opera House roof weighs more than 161,000 tons.

There are 1500 species of Australian spiders.

Australia has the world's largest population of wild camels with one hump.

• Tasmania has the cleanest air in the world.
• The Great Barrier Reef has a mailbox. You can ferry out there and send a postcard, stamped with the only Great Barrier Reef stamp.

Opals in our eyes

produces 95% of the world's precious opals and 99% of its black opals.

World’s largest opal, weighing 5.27 kg, was found in 1990

Merinos and cattle calls

Australia's 85.7 million sheep (mostly merinos) produce most of the world's wool.

With 25.4 million head of cattle, Australia is also the world's largest exporter of beef.

Natural legends
Queensland’s Great Barrier Reef is home to

-World’s largest oyster, weighing up to 3 kilograms,
-World’s longest earthworm, stretching up to 4 metres or 13 feet.

-Heaviest crab weighs up to 14 kilograms

Aboriginal people have lived and thrived on this continent for more than 50,000 years.

-invented the aerodynamic boomerang & type of spear thrower called the woomera.

Other Inventions

notepads (1902), penicillin (1940), aspirin (1915), plastic disposable syringe (1949), wine cask (1965), bionic ear (1978), dual-flush toilet flush (1980), long-wearing contact lenses (1999), surf lifesaving reel (1906)

Koala
is a unique Australian marsupial.
are only active for around 2 hours a day
get all their fluids from eating eucalyptus leaves.
sometimes stays in the same tree for days.

Possum

are small marsupials with brown or grey fur.
hide in a nest in a hollow tree during the day & foraging for food at night.
Aboriginal people used possum-skin to make cloaks

Kookoburra
Is the world’s largest kingfisher.
kookaburras have a stout and compact body, short neck, long & pointed bill and short legs.
are best known for their hysterical, human-sounding laughter at dusk and dawn.
They also often sing as a chorus to mark their territory and will eat almost everything.

Lyrebird

is a ground-dwelling Australian bird, known for its ability to mimic any sound it hears– from car engines and fire alarms to crying babies.
The lyrebird is named after the male’s spectacular, 16-feathered tail, which was thought to resemble a lyre in the 1800s.

Tasmanian Devil
appearance of a small, stocky dog.
has a broad head, thick tail and coarse, black fur.
was given name by early European settlers,
world’s largest carnivorous marsupial

who were haunted at night by its screeches & demonic growls.
is actually a shy creature.

Dingo

is Australia’s wild dog, though is not native to the continent.
are carnivores, commonly feeding on kangaroos, wallabies, cattle, wombats and possums.
are highly social creatures and form stable packs with clearly defined territories where possible.
communicate through howling and whimpering and bark less than domestic dogs.

Kangaroo

Kangaroos are the only large animals to travel by hopping & breeding adult males often fight by boxing with their front paws & kicking their back legs.
There are 55 kangaroo species spread across Australia.
Some kangaroos can jump 30 feet.

Emu
is a large, brown, soft-feathered, flightless bird.
Emus grow up to two metres tall and have three toes and long legs that allow them to run very fast, up to 50km per hour.
The female emu is larger than the male and lays up to 20 large, dark green eggs. Emu feeds on grass, leaves and small insects.

Platypus
are small, dark-brown, furry, egg-laying mammals with webbed paws and a duck-like beak.
live in burrows which they dig into the banks of rivers.
are diving animals, & can stay under water for up to 15 mins.

Wallaby

name comes from Sydney’s Eora Aboriginal tribe.
are smaller than a kangaroo or wallaroo.
Very small forest-dwelling wallabies are known as pademelons.

Wild Cats

• Common physical traits of big cats are keen eyesight, round heads, whiskers, and retractable claws.
• Big cats have a flexible hyroid bone, enabling them to roar. Small cats have a rigid hyroid bone, which allows them to purr rather than roar

Lion

• Unlike many wild cat species, lions live and hunt in social groups called prides, —
• Around 20,000 lions found primarily in 4 African states, South Africa, Botswana, Tanzania, & Kenya.
• Can weigh anywhere between 300 and 500 lbs and life 12-16 yrs in wild, 25 yrs in captivity.
• fawn / tawny in color, with black on their extremities and mane.
• Males in the pride protect their territory, & females do the hunting.
• An adult lion's roar can be heard up to 5 miles (8 kilometers) away.
• Unlike other cats, lions have a tuft of hair at the end of their tails.

Tiger

Biggest of the big cats, also rank among the most endangered big cats.

Approx. 5,000 - 7,000 tigers now live in the wild,

A tiger's stripes are like fingerprints—no two animals have the same pattern.

Tigers have been hunted for their skin, bones, & other body parts, used in traditional Chinese medicine.

Tigers are excellent swimmers & do not avoid water and live solitarily

Can weigh up to 600 lbs! and live solitarily.

Bengal tiger lives in forested areas around the Indian sub-continent.
— Population estimates of approx. 4,000

Indo-Chinese tigers live forested areas of South East Asian states such as China, Thailand and Myanmar.
-Ranks as the 2nd most populous with maybe around 2,000 living in the wild.

Sumatran tigers live on the island of Sumatra, Indonesia.
-are the smallest of the tiger species & there might be around 400 living in the wild.

Siberian or Amur tigers hold the distinction of being the biggest of the world's big cats.
-They live along the forests of the Amur River, a natural boundary line between Russia and China on the east coast.
-They are endangered, however, population estimates show that 400-500 remained steady.

South China tigers live in south-central China,
-are commonly recognized as the most endangered tigers in the world.

3 species have already gone extinct:
— Bali Tiger * Javan Tiger * Hyrcanian Tiger

Cheetah

Ranked as the smallest, with an avg. size comparable to a big dog (approx. 4 feet long and 80 to 140 lb).

• Cheetahs are the fastest the world's fastest land mammal, reaching speeds of 70 miles /hr.
• Cheetahs do not roar, as the other big cats do. Instead, they purr.
• The mountain lion and the cheetah share an ancestor.
• In one stride, a cheetah can cover 23 to 26 feet (7 to 8 meters).
• They look a lot like the leopard but are more long and sleek.
• They are not built for, nor are they good at climbing.
• Cheetahs are very timid
• They feed mostly on gazelle and impala and are solitary hunters.
• The black “tear” going from their eye down the side of their nose is to help keep sunlight out of their eyes.
• In the wild, they would much rather prefer switching to a new food source rather than fighting any other predator for it.
• Wild cheetah population currently ranges between 9-12000. Namibia is home to the largest cheetah population (approximately 2,500).

Jaguar

New world cat found from the Southwestern United States, south to Argentina.

• Very adaptable cat, at home in a variety of habitats, as long as it contains an adequate supply of food and water.
• Is a stocky, muscular cat distinguished by its rosette markings, though there are also black jaguars (often mistakenly called black panthers) that appear to be solid black but actually have faint rosettes.
• Live and hunt in dense forests and kill their prey with one bite to the head to pierce the skull.
• It is said that they have no rivals because no other creature can conquer them.
• The name "jaguar" comes from a Native American word meaning "he who kills with one leap."
• Fossil records from two million years ago show evidence of jaguars.
• Considered vulnerable species. They are listed as endangered in the United States.

Leopard
The name leopard also refers to a group of big cats with the Latin name Panthera pardus.
Leopards weigh between 100 and 200 lbs.

• They have brown coats covered in black spots.
• Leopards hunt small to medium prey and are known for dragging their kill up into a tree to relax and enjoy their meal.
• Leopards are good swimmers, though not terribly fond of water.
• The strongest climber among the big cats, a leopard can carry prey twice its weight up a tree.
• Identified as a near threatened species.
• The Amur Leopard (Asia), the Javan Leopard, and the South Arabian Leopard are listed as critically endangered, moving to the verge of extinction.

Snow Leopard

• Lives in mountains of Central Asia
• Is a rare cat that lives in harsh, remote environments.
• Have white, yellowish, or gray fur with dark gray to black spots & rosettes.
• Coat developed as camouflage and protect in their snowy and rocky environment.
• Fur on their bellies can be 5” long.
• They can leap 6 times the distance that their body is long!
• Have large snowshoe feet,
• Their tails are as long as the length of their body,
• Average weight between 77 and 121 lbs
• Estimated population of about 2,500
• An endangered species

Clouded Leopard

Medium sized cats marked with over sized spots or clouds.

Native to the tropical forests of Southeast Asia, catching most of their prey in trees.

• Gets its name from its distinctive cloud-like markings. They have small dark spots interspersed with large dark spots that are lighter in the center (clouds).
• The tail, which is as long as the length of their body, is ringed.
• Legs are short, with their back legs being slightly longer than the front,
• Weigh between 22 and 45 lbs.
• They have the longest teeth of any of the cat species.

Mountain Lion or Cougar
Also known as the puma or mountain lion

• Is tawny in color with a white belly.
• Their body length is about 4 ½’ long, not including their tail.
• Males can grow up to 8 feet in length
• They can weigh anywhere from 75 to 250 lbs.
• Cougars are agile and can jump about 18’ high!
• Interestingly, cougars have a poor sense of smell

7 Natural Wonders of the World

Thursday July 8, 2010










Aurora Borealis: Northern Lights

Also known as polar auroras

frequently appear as diffused glow lighting up the horizon

• are naturally occurring lights that create intriguing and spectacular displays in the sky
• The northern lights are the most notable, but a southern aurora does occur in the southern hemisphere
• No specific or consistent measurements
• Appear as glowing sheets or dancing waves
• The colours of the aurora are either a combination of red and green light, or red and blue light.
• The name “Aurora Borealis” is credited to Galileo Galilei (1616) and means “northern dawn.”

Paricutin Volcano, Mexico

A cinder cone volcano in Michoacán, Mexico
-cinder cones are simple volcanoes which have a bowl-shaped crater at the summit
only grow to about a thousand feet, the size of a hill
they usually are created of eruptions from a single opening
▫ made of piles of lava, not ash

• Official height approximately 10,000 ft or 3,000 meters
• Last erupted in 1952
• Was also fast growing reaching three-fourths of its size within the first year.
• Birth witnessed by mankind
• The Paricutin eruption took place between February 1943 and February 1952.
• The Paricutin volcano grew out of a cornfield.

Grand Canyon, Arizona USA

Is a massive gorge located in the state of Arizona in the United States, and was created by the Colorado River
Canyon is 277 miles (446 km) long

• Width ranges from 4 to 18 miles (6.4 to 29 km)
• Depth is over one mile (1.83 km)
• Majority is housed within Grand Canyon National Park
• Prehistoric Pueblo Peoples are living in the canyon (900 years ago) .
• Grand Canyon established as a forest preserve in 1892.
• Scattered rocks located at the bottom of the canyon date back as far as 2 billion years.

Victoria Falls, Zimbabwe

Also called Mosi-oa-Tunya meaning “smoke that thunders”

Largest waterfall based on width and height

• One mile wide (1.7 km) and 360 feet high (108 meters)
• Two national parks (Zambia) and (Zimbabwe) protect the falls
• Rain 24/7 -Because of the spray from the falls – the Rain Forest at Victoria Falls is the only place on earth that it rains 24 hours a day – 7 days a week
• During a full moon you can see a moonbow at Victoria Falls. This can been seen through the spray at night instead of during the day as a solar rainbow. The day light rainbow is exactly the same as the full moonlight rainbow: the colour scheme and the shape of the curvature are the same.

Mount Everest, Nepal

• Highest mountain in the world, represents the highest spot on the earth's surface
• Summit reaches a peak of 29,029 feet (8,848 m)
• Located in the Himalaya mountains on the border between Nepal and Tibet
• Also known as Chomolungma
• As per records that belong to the Nepalese Government, it was a 15-year-old Sherpa girl who turned out to be the youngest person to climb Mount Everest.
• Their records also claim, Samantha Larson, an 18 year old foreigner from California, was the youngest ever foreigner to climb the Mount Everest in 2007.
• Australian climber Christian Stangi was recorded to have made the fastest ascent in 2007.
• Bahadur Sherchan remains to be the oldest climber at 76 years to successfully climb Mount Everest. He achieved this feat on 25 May 2008.
• Mount Everest is also home to a very minute black jumping spider. These spiders hide in crevices and feed on frozen insects. Their food depends largely upon what is blown by the wind into the specific area.
• Soon to be called "World's Highest Garbage Dump."
• According to estimates, there are nearly 120 tons of litter and 120 dead bodies on Mt. Everest.
  

Great Barrier Reef, Australia

Largest coral reef system in the world
Consists of over 2,900 separate reefs
Includes 900 islands
Stretches over 1,600 miles (2,600 km)
Can be seen from outer space

• Supports one of the most diverse ecosystems in the world
• Some of the largest populations of Dudongs visit the Great Barrier Reef
  • Dudongs are classified as marine mammals and are related to the elephants.
• Great Barrier Reef was formed around 18 million years ago
• Crown-of-Thorns Seastar is only found in this habitat and a native species to Australian waters.
  -"outbreaks" occur in which the population becomes unbalanced and threatens to destroy areas of the reef at a rate faster than that at which it can rebuild itself

Harbor of Rio de Janeiro, BRAZIL

• Was created by erosion from the Atlantic Ocean
• Also known as Guanabara Bay
• Largest bay in the world based on volume of water
• Is surrounded by gorgeous granite monolith mountains
• Rio de Janeiro translates "river of January" in Portuguese
• There is some error in the name; Rio de Janeiro means River of January, but it is on the shores of Guanabara Bay.
• The Portuguese sailors who came early were in a naming spree; found a calm water body within 20 miles of the shore they took it for the mouth of a river and named it Rio de Janeiro -the River of January as they discovered it in the month of January.
• Now the bay is Guanabara Bay its original name called by the natives and the huge natural harbor functioning within the bay and the nearby city all are ‘Harbor of Rio de Janeiro’.
• It is the capital of the Brazilian state with the same name -Rio de Janeiro.
  

History of Mathematics

Thursday, July 1, 2010


Mathematics: Originates from Greek root words that tell us that the subject is about learning, not about numbers.
Babylonian mathematicians working in 2000 B.C.E., developed theories that were later tested and built upon by dedicated Greek thinkers.
Indian mathematicians working from 1500-1600 B.C.E. developed the concepts of zero and infinity as well as negative, irrational, and binary numbers.
The Arab countries were known to use three different types of counting systems in the eleventh century.



Mediums Used

• Babylonians used imperishable baked clay tablets
• Egyptians used stone and a kind of reed, papyrus.
• Early Chinese and lndians used very perishable media like bark and bamboo.
  

Mayan Numeral System has a symbol for '0'. This is written very simply by dots and dashes.
Roman Numeral System was decimal system, using letters. This way disabled them from calculating multi-digits number so they used abacus.
Hindu-Arabic Numeral System- Hindus invented it and Arabs spread it Europe

Famous Mathematicians
Isaac Newton – Calculus and Laws of motion
Brahmagupta – to treat zero as a number in its own right.
Gauss – Prince of Mathematics
Pythagoras –Father of Numbers

The abacus is a counting tool. The user of the abacus is called Abacist.

Kakuro Puzzle
Fill in the blank squares with numbers from 1 to 9, so that the numbers add up to the total required both horizontally and vertically. Each number can only be used once in each row or column. You will need to use both your adding and logic skills!

Soma Cubes
The Soma cube is not really a cube. It's a puzzle like Tangram. You have to rearrange puzzle pieces to form other figures. In fact there are 7 Soma-pieces like Tangram. But unlike Tangram the pieces from the Soma Cube are three-dimensional. The Soma-cube was conceived, according to Martin Gardner, by the Danish writer Piet Hein in 1936.

The Magic Square
A magic square is an arrangement of the numbers, with each number occurring exactly once, and such that the sum of the entries of any row, any column, or any main diagonal is the same.

Rubik Cube
In 1974, Rubik creates the first working prototype of the cube. This is the official birth date of the world’s favourite toy. In a classic Rubik's Cube, each of the six faces is covered by nine stickers, among six solid colours (traditionally white, red, blue, orange, green, and yellow)