What is irrigation?

Irrigation is the act of artificially applying water to soil to allow plant growth. This can also include applying water to a lawn or garden. The term usually refers to providing large amounts of ... More

Why is there salt used in ice cream making?

Salt is used in ice cream because of a special property it possesses: It lowers the freezing temperature of water. Consider making the most basic ice cream. You would mix together milk or cream, ... More

What caused humans to become more advanced than chimps?

Genetic changes in areas that affect the appetite may be the reason humans became more advanced than chimps. Primatologists believe that almost 2 million years ago, human males began to share more ... More

How does the last common ancestor relate to evolution?

In researching how life-forms evolve, scientists have identified linear progressions in which a singular form developed into another form or more. Even though some of the new life-forms either ... More

What causes genetic differences between humans and chimps?

Although gene sequences are similar in humans and chimps, there can be a significant difference in copy number variations. The DNA code can have deletions, repetitions and backward sequences. ... More

How are Fibonacci numbers expressed in humans?

Fibonacci was born Leonardo Pisano in 1175 in Pisa, better known for its leaning tower. Little did the town's citizens know late in the 12th century that one of their own would become famous for a ... More

What causes St. Elmo's Fire?

St. Elmo's Fire is caused by a great imbalance in electrical charge. During a thunderstorm, air becomes ionized, which means it becomes a good conductor of electricity. When there is a dramatic ... More

Where did Homo sapiens come from?

The prevailing theory among scientists is the "out of Africa theory" or the replacement theory, which suggests that humans evolved in Africa and migrated to other lands between 56,000 and 200,000 ... More

Could fossil fuel be synthesized?

It has been theorized that it may be possible to synthesize fossil fuels. To do so, we would first have to capture carbon dioxide, which is already being done with post-combustion carbon capture ... More

What is desertification?

Desertification refers to land degradation that occurs in arid and semi-arid areas known as drylands. Land degrades in such areas when land clearing, urbanization and unsustainable agricultural ... More

How is wind speed measured?

Wind speed was originally categorized according to the Beaufort scale. Developed in 1806 by Adm. Sir Francis Beaufort, this system ranges from zero to 12, with a higher number indicating greater ... More

What is the purpose of Norway's doomsday vault?

The Svalbard International Seed Vault in Norway -- a.k.a the "doomsday vault" -- exists to protect agricultural biodiversity. In the event that a catastrophe damaged or destroyed all plant life, ... More

What is the Rankine temperature scale?

The Rankine scale came out of research in thermodynamics. It was named for William J.M. Rankine, a Scottish physicist and engineer, and is used mostly in American engineering. This scale has a ... More

What are the polar easterlies?

The polar easterlies are one of the five primary wind zones, known as wind belts, that make up our atmosphere's circulatory system. This particular belt of wind begins at approximately 60 degrees ... More

How do thermometers measure temperature?

Thermometers do not measure how hot or cold an object is. They measure how temperature changes expand and contract the material used in the mechanism or instrument. Expansion and contraction are ... More

What is a thermograph?

A thermograph is a device that records temperatures over a fixed period of time. It consists of a rotating drum or disk and a stylus or pen. Often, a bimetal mechanism for measuring temperature ... More

How do resistance thermometers work?

Resistance thermometers measure changes in the electrical resistance of metal materials or thermistors. A thermistor is a type of resistor made of semiconducting material. The mechanism consists ... More

What makes Norway an ideal location for the doomsday vault?

Norway has a cluster of islands in the Arctic Ocean that boast perpetually frozen temperatures. Specifically, a mountain called Spitsbergen has the coldest, most frigid temperatures. If the ... More

Are there animals on islands?

Yes, there is wildlife on islands. A continental island typically has the same types of plants and animals as the neighboring continent to which it was once connected. This is because the wildlife ... More

How do people enter and exit an underwater habitat?

Interestingly, the entrance to many underwater habitats is on the bottom, rather than a doorway on the sides or the top. Because the pressure level is the same both inside and out of the chamber, ... More

What is an underwater habitat?

Underwater habitats are special underwater chambers in which divers can live for extended periods of time without necessarily needing to come up for air. These chambers feature the same level of ... More

Are there any examples of speciation going on now?

While its long-term effects have yet to surface, there is one place scientists are keenly watching in an attempt to understand speciation. In 1995, Hurricane Marilyn passed through the Caribbean, ... More

What is the future of the theory of evolution?

The theory of evolution seeks to explain the origin of life on Earth and the origin of different species. While most of the scientific community has regarded evolution as fact for more than a ... More

Why are siblings different from each other?

Siblings are different from each other because of how sexual reproduction works. People's cells have chromosomes that contain their DNA, and these chromosomes are organized into 23 pairs. When ... More

What is the history of biomimicry?

Biomimicry -- applying nature's solutions to human problems -- can be traced back to early humans. They observed animals and mimicked their hunting, shelter and survival behaviors. In the 15th ... More