Thursday, December 30, 2010

2011-Rabbit Year

A pet rabbit is dressed as Santa Claus to celebrate Christmas and the Year of the Rabbit at a pet rabbit shop in Yokohama, south of Tokyo. The year 2011 is the Year of the Rabbit on the Chinese zodiac calendar.

‘Jellyfish Joyride’ a threat to the oceans

Early action could be crucial to addressing the problem of major increases in jellyfish numbers, which appears to be the result of human activities. New research led by CSIRO Climate Adaptation Flagship and University of Queensland scientist, Dr Anthony Richardson, presents convincing evidence that this 'jellyfish joyride' is associated with over-fishing and excess nutrients from fertilizers and sewage.

Dense jellyfish aggregations can be a natural feature of healthy ocean ecosystems, but a clear picture is now emerging of more severe and frequent jellyfish outbreaks worldwide,' Dr Richardson says.

The new research, by Dr Richardson and colleagues at the University of Miami, Swansea University and the University of the Western Cape, has been published in the international journal.

Fish normally keep jellyfish in check through competition and predation but overfishing can destroy that balance,' Dr Richardson says. Climate change may favor some jellyfish species by increasing the availability of flagellates in surface waters - a key jellyfish food source. Warmer oceans could also extend the distribution of many jellyfish species.

'Mounting evidence suggests that open-ocean ecosystems can flip from being dominated by fish, to being dominated by jellyfish,' Dr Richardson says.

Tuesday, December 28, 2010

Finest Chocolate from Cacao Tree

“The production of high quality chocolate, and the farmers who grow cacao tree, will benefit from the recent sequencing and assembly of the chocolate tree genome”, according to an international team led by Claire Lanaud of CIRAD, France, with Mark Guiltinan of Penn State, and including scientists from 18 other institutions.

The team sequenced the DNA of a variety of Theobroma cacao, considered to produce the world's finest chocolate. Many growers prefer to grow hybrid cacao trees that produce chocolate of lower quality but are more resistant to disease.

"Fine cocoa production is estimated to be less than 5 percent of the world cocoa production because of low productivity and disease susceptibility," said Guiltinan, professor of plant molecular biology.

The trees are also seen as an environmentally beneficial crop because they grow best under forest shade, allowing for land rehabilitation and enriched biodiversity.

The team's work identified a variety of gene families that may have future impact on improving cacao trees and fruit either by enhancing their attributes or providing protection from fungal diseases and insects that effect cacao trees.

Monday, December 27, 2010

Brain is not fully mature until 30s and 40s

Professor Sarah-Jayne Blakemore, a neuro scientist with the Institute of Cognitive Neuroscience at University College London, said until around a decade ago many scientists had "pretty much assumed that the human brain stopped developing in early childhood," but recent research has found that many regions of the brain continue to develop for a long time afterwords.

The prefrontal cortex is the region at the front of the brain just behind the forehead, and is an area of the brain that undergoes the longest period of development. It is an important area of the brain for high cognitive functions such as planning and decision-making, and it is also a key area for social behavior, social awareness, for empathy and understanding and interacting with other people, and various personality traits. Prof. Blakemore said the prefrontal cortex “is the part of the brain that makes us human,” since there is such a strong link between this area of the brain and a person’s personality.

Prof. Blakemore said brain scans show the prefrontal cortex continues to change shape as people reach their 30s and up to their late 40s. She said the region begins to change in early childhood and then is reorganized in late adolescence but continues to change after that.

The research could explain why adults sometimes act like teenagers, sulking or having tantrums if they do not get their own way, and why some people remain socially uncomfortable until they are well out of their teens.

Monday, December 20, 2010

Newly Discovered Species of 2010

Tree Frog

O'Shaughnessy's Dwarf Iguana

Glass frog

Lungless Salamander

Eyed gecko

Stick Insect

The slug sucking snake

Rain Frog

Monday, December 13, 2010

Black Smokers From Under the Sea

What is a black smoker?

You've probably seen or heard of natural hot springs on land, like Old Faithful at Yellowstone National Park. Similar phenomena occur under the oceans within mid-ocean ridge volcanoes and are called deep-sea hydrothermal (hot water) vents. They are known as black smokers.

These black smokers are chimney like structures made up of sulfur-bearing minerals or sulfides that come from beneath Earth's crust. They form when hot (roughly 350¡C); minerl-rich water flows out onto the ocean floor through the volcanic lava on a mid-ocean ridge volcano. Sulfide minerals grow or crystallize from the hot water directly onto the volcanic rocks at the place where the hot, mineral-rich water flows from the ground. This crystallization forms a hollow, chimney like sulfide structure through which the hot water continues to flow. As the hot, mineral-rich water rushes out of this chimney and mixes with the cold ocean bottom water, it precipitates a variety of minerals as tiny particles that make the vent water appear black in color. This is why these sulfide chimney structures are called black smokers.

Where is the black smoker?

Deep-sea hydrothermal vents occur along the mid-ocean ridges. Several different vents have been discovered since the first site was found in 1977 near the Galapagos Islands by earth scientists in the small research submersible ALVIN. One reason that relatively few sites have been observed is that scientists have explored only a small portion of the 50,000 kilometers of mid-ocean ridges. So it is likely that as scientists explore more of the mid-ocean ridges they will discover more deep-sea hydrothermal vent sites. In fact, scientists also have found that not every ridge has a deep-sea hydrothermal vent site. Scientists don't know exactly why some ridges have deep-sea hydrothermal vents and others don't. Two areas of active research are exploration of ocean basins and investigation of the processes that cause deep-sea hydrothermal vents. This expedition will make observations and collect samples that scientists will use to learn more about the processes at deep sea hydrothermal vent sites.

Why do we need to know about black smoker?

Large amounts of heat and chemical mass are transferred from deep within Earth to Earth's surface through deep-sea hydrothermal vents. The chemistry of ocean water is controlled in part by this process. Thus, understanding how deep-sea hydrothermal vents work is critical to understanding the dynamic nature of our planet.

Deep-sea hydrothermal vents support extraordinary ecosystems deep beneath the surface of the oceans. These ecosystems are the only communities on Earth whose immediate energy source is not sunlight. Life on Earth, and even possibly on other planets, may have formed in environments similar to these.

The life-forms that support the food chain at deep-sea hydrothermal vents also participate in the formation of the minerals that make up the sulfide chimney structures. Understanding this biochemical mineral formation process will help us to understand ore (minerals of economic interest) formation processes in general.

Monday, December 06, 2010

Coconut a fruit, nut or seed?

Botanically speaking, a coconut is a fibrous one-seeded drupe, also known as a dry drupe. However, when using loose definitions, the coconut can be all three: a fruit, a nut, and a seed.

Botanists love classification. However, classification of plants can be a complicated matter for the average person. Coconuts are classified as a fibrous one-seeded drupe. A drupe is a fruit with a hard stony covering enclosing the seed (like a peach or olive) and comes from the word drupa meaning overripe olive. A coconut, and all drupes, have three layers: the exocarp (outer layer), the mesocarp (fleshy middle layer), and the endocarp (hard, woody layer that surrounds the seed).

The coconut we buy in the store does not resemble the coconut you find growing on a coconut palm. An untouched coconut has three layers. The outermost layer, which is typically smooth with a greenish color, is called the exocarp. The next layer is the fibrous husk, or mesocarp, which ultimately surrounds the hard woody layer called the endocarp. The endocarp surrounds the seed. Generally speaking, when you buy a coconut at the supermarket the exocarp and the mesocarp are removed and what you see is the endocarp.

Some scientists like to refer to the coconut as a water dispersal fruit and seed. A seed is the reproductive unit of a flowering plant. From a reproductive point of view, a seed has the “baby” plant inside, with two basic parts: the embryo root (hypocotyl) and the embryo leaves (epicotyl). In the coconut’s case, if you look at one end of the coconut, you’ll see three pores (also called eyes). The coconut seed germinates and a shoot emerges from one of the pores. In addition to the “baby” plant in the seed, there is the food to kick off its life called the endosperm. The endosperm is what makes up most of the seed and, in the coconut’s case, is the yummy white stuff we eat.

The word coconut itself can also be confusing because the word “nut” is contained in the word. A nut can be defined as a one- seeded fruit. With that loose definition, a coconut can also be a nut. However, a coconut is not a true nut. A true nut, such as the acorn, are indehiscent or do not open at maturity to release its seeds. The seeds are released when the fruit wall decays or are digested by an animal.

Yet another interesting aspect of the coconut that has baffled scientists for over 200 years is where did it originate? Is it of Old World or New World origin? Scientists have used art, botany, entomology, etymology, folklore, fossils, genetics, and travel records to try to figure out where the coconut first appeared.

Odoardo Beccari, a renowned palm specialist from the early 20th century, suggests that the coconut is of Old World origin and more than likely came from the Indian Archipelago or Polynesia. To strengthen his argument, there are more varieties of coconut palms in the Eastern hemisphere than in the Americas.

However, some scientists (O.F. Cook , H.B. Guppy, K.F.P. von Martius,) argue that the coconut is of New World origins, having migrated westward across the Pacific.

Interesting Coconut Facts

* Every bit of the coconut is used. As a result, coconuts are called the “Tree of Life” and can produce drink, fiber, food, fuel, utensils, musical instruments, and much more.

* When intra-venous (IV) solution was in short supply, doctors during World War II and Vietnam used coconut water in substitution of IV solutions.

* Botanically, the coconut palm is not a tree since there is no bark, no branches, or secondary growth. A coconut palm is a woody perennial monocotyledon with the trunk being the stem.

* Possibly the oldest reference is from Cosmas, a 5th century AD Egyptian traveler. He wrote about the “Indian nut” or “nut of India” after visiting India and Ceylon, Some scholars believe Cosmas was describing a coconut.

* Soleyman, an Arab merchant, visited China in the 9th century and describes the use of coir fiber and toddy made from coconuts.

* In 16th century, Sir Francis Drake called coconut “nargils”, which was the common term used until the 1700’s when the word coconut was established.

* It takes 11 -12 months for the coconut to mature.

* At one time scientists identified over 60 species of Cocos palm. Today, the coconut is a monotypic with one species, nucifera. However, there are over 80 varieties of coconut palms, which are defined by characteristics such as dwarf and tall.

* Coconut growing regions are as far north as Hawaii and as far south as Madagascar.

Wednesday, December 01, 2010

Listen to Song of the Sun

To most of us, the sun seems to dangle in space silently without making so much as a peep. Nevertheless, "the sun is a very noisy place," said Scott McIntosh of the National Science Foundation -supported National Center for Atmospheric Research.

The sun sounds like a low hum punctuated by frequent rhythmic, bass-y thumps. Sun generate its sound composed of gases; the sun's core contains a giant nuclear fusion factory, where hydrogen is pressed into helium at temperatures of about 27,000,000° Fahrenheit (15,000,000° Celsius). The energy of this nuclear fusion factory generates convection that reaches all the way to the sun's surface.

The convection follows regions, or cells, and is driven by gas that roils and boils, similar to the boiling of water in a pot. The motion of the gas within the convection cells changes the light waves emitted by the surface of the sun.

Scientists measure the changing light waves using an instrument called a dopplergraph that is mounted on a spacecraft called the Solar and Heliospheric Observatory (SOHO). The measured light changes are translated into motion (sound) waves by computer models that capture the relationships between light waves and sound waves.

Because the resulting sound waves are at a frequency too low to be heard by humans, the signals are sped up to become audible. The result: an inferred composite of solar sound waves that includes "all kinds of frequencies," McIntosh said.

The sun's serenade can only be inferred because there is no air in the 93 million miles of space between the Earth and sun. And since sound cannot travel through a vacuum, the sun cannot be directly heard from Earth.

McIntosh compares the multi-frequency song of the sun to the ringing of cathedral bells that each hit different notes. Just as cathedral bells get louder and chime out certain pitches when certain bells are simultaneously rung, the sun belts out rhythmic bass thumps over its background hum when certain frequencies overlap with one another.

The relatively recent discovery and understanding of the sun's waves are enabling scientists to, for the first time, go under the surface and actually "see" inside the sun. With the help of the dopplergraph, which is used to track the time taken by certain waves to travel through the sun and back--similar to the way that seismographs are used to track waves of energy traveling below and along the Earth's surface (in order to help scientists detect earthquakes).

From the dopplergraph measurements, scientists can deduce the temperature, chemical composition and motions of gases from just below the sun's surface to close to its core. This technique is also being used to investigate the surfaces and interiors of other stars besides the sun.