Biology: Sand Tiger Shark

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Sand tiger shark: upper body.

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The Sand Tiger Shark is a grayish-brown colored shark with a white underside. They are called Sand Tiger Sharks because or their coastal habitat near the shore. Despite their mean look the only attack humans if provoked.

They grow to 2 - 3.2 (6.5 - 10.5) and live 15 years or more. Sand Tiger Sharks are known to gulp air from the surface. They store the air in their stomachs, which allows them to float motionless in the water, seeking prey. They are voracious predators, feeding at night and generally staying close to the bottom. Their staple is small fish, but they will eat crustaceans and squid as well. They occasionally hunt in groups, and have even been known to attack full fishing nets.

Although this species is widespread and is not widely fished for food, it has one of the lowest reproduction rates of all sharks and is susceptible to even minimal population pressure. For this reason, it is listed as vulnerable and is protected in much of its range.

Sources: National Geographic Image: Wikipedia

Social Studies: English idioms

Wiktionary has an A -Z list of idioms. Its good if your trying to learn English or if your just curious. I know a lot of them I've never heard of.

Link: Wiktionary

Biology: Neat Facts

• Escherichia coli (E. coli) bacteria is found in the lower intestine. In fact most strains of E. coli are harmless bur some strains are harmful. - Wikipedia
  

• Bacterial infection causes stomach ulcers 80% of the time. (1) One of these is the Helicobacter pylori (H. pylori). Over 50% of the worlds population is infected with this bacteria. But strangely over 80% of these are asymtomatic (2) (show no syptoms). - Wikipedia 1 and 2

Science: Needle ice

Needle ice is a phenomenon that occurs when the temperature of the soil is above 0°C and the surface temperature of the soil is below 0°C. The subterranean moisture is brought to the surface via capillary action.

The ice needles are typically a few centimetres long. While growing, they may lift or push away small soil particles. On sloped surfaces, needle ice may be a factor contributing to soil creep.

Sources: Wkipedia

Biology: Dog communication

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The dog is showing signs of heavy aggression.

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Here are some things dogs try to express and how they express them. These are often used in dog to dog communication but you too can use these and the others found at the source to understand a dog. (See the bottom of the post under "Sources".)

Happiness/excitement

• Large fast wags of the tail.
• Panting with lips relaxed covering the teeth (not to be confused with a snarl where the lips are retracted showing the teeth).
  
• Stamping its feet, alternating from left to right.
• Short sharp barks.

Playfulness

• Panting with lips relaxed covering the teeth.
• Large fast wags of the tail.
• Intense growl, without showing any teeth.

Anger/Aggression

• Lowered head.
  
• Lowered body.
  
• Raised back hair.
  
• Ready to pounce.
  
• Foot pointing.
• Focused attention.

Just remember LLRRFF. See photo at top of blog post.

Other signs are:

• Soft, low-pitched growl.
• Showing teeth.
  

Fear/Timidness

• Tail down or between legs.
• Ears down.

You probably noticed that some signs are mentioned more than once, that's because, like human expressions, these body movements and vocalizations can have more than one meaning, it all depends on the context.

Sources: Wikipedia

Social Studies: Ham

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Greeting Ham after his landing in the Atlantic, January 31, 1961.

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Ham is a lunch meat. Ham is also the name of the first chimpanzee in space.

Ham was born July 1956 in Cameroon, captured by animal trappers and sent to Rare Bird Farm in Miami, Florida.He was purchased by the United States Air Force and brought to Holloman Air Force Base in 1959. Officially, Ham was known as #65 before his flight, and only renamed "Ham" upon his successful return to earth.

H.A.M. stands for Holloman Aerospace Medical Center the lab where he was trained.

Beginning in July 1959, the two-year-old chimpanzee was trained at the Holloman Air Force Base Aero Medical Field Laboratory to do simple, timed tasks in response to electric lights and sounds.

On January 31, 1961, Ham was secured in a Project Mercury capsule labeled MR-2 and launched from Cape Canaveral, Florida, into outer space. Ham had his vital signs and tasks monitored using computers back on Earth. The capsule suffered a partial loss of pressure during the flight, but Ham's space suit prevented him from suffering any harm. Ham's lever-pushing performance in space was only a fraction of a second slower than on Earth, demonstrating that tasks could be performed in space. Ham's capsule splashed down in the Atlantic Ocean and was recovered by a rescue ship later that day. He only suffered a bruised nose. His flight was 16 minutes and 39 seconds long.

After the flight, Ham lived for 17 years in the National Zoo in Washington, D.C., then at the North Carolina Zoo before his death at the age of 26 on January 19, 1983.

Sources: Wikipedia

Chemestry: Electroplating

Electroplating is using electrical current to coat a metal with a thin layer of another metal.

The anode and cathode in the electroplating cell are both connected to an external supply of direct current - a battery or, more commonly, a rectifier. The anode is connected to the positive terminal of the supply, and the cathode (article to be plated) is connected to the negative terminal. When the external power supply is switched on, the metal at the anode is oxidized from the zero valence state to form cations with a positive charge.

These cations associate with the anions (with a negative charge) in the solution. The cations are reduced at the cathode to deposit in the metallic, zero valence state. The build up of these atoms create a thin layer.

Sources: Wikipedia