What is Evolution?

Do you know what is evolution? If NO! than this is for you.

Human evolution is the lengthy process of change by which people originated from apelike ancestors. Scientific evidence shows that the physical and behavioral traits shared by all people originated from apelike ancestors and evolved over a period of approximately six million years.

One of the earliest defining human traits, bipedalism — the ability to walk on two legs — evolved over 4 million years ago. Other important human characteristics — such as a large and complex brain, the ability to make and use tools, and the capacity for language — developed more recently. Many advanced traits — including complex symbolic expression, art, and elaborate cultural diversity — emerged mainly during the past 100,000 years.

Humans are primates. Physical and genetic similarities show that the modern human species, Homo sapiens, has a very close relationship to another group of primate species, the apes. Humans and the great apes (large apes) of Africa — chimpanzees (including bonobos, or so-called “pygmy chimpanzees”) and gorillas — share a common ancestor that lived between 8 and 6 million years ago. Humans first evolved in Africa, and much of human evolution occurred on that continent. The fossils of early humans who lived between 6 and 2 million years ago come entirely from Africa.

Most scientists currently recognize some 15 to 20 different species of early humans. Scientists do not all agree, however, about how these species are related or which ones simply died out. Many early human species — certainly the majority of them – left no living descendants. Scientists also debate over how to identify and classify particular species of early humans, and about what factors influenced the evolution and extinction of each species.

Early humans first migrated out of Africa into Asia probably between 2 million and 1.8 million years ago. They entered Europe somewhat later, between 1.5 million and 1 million years. Species of modern humans populated many parts of the world much later. For instance, people first came to Australia probably within the past 60,000 years and to the Americas within the past 30,000 years or so. The beginnings of agriculture and the rise of the first civilizations occurred within the past 12,000 years.

Paleoanthropology

Paleoanthropology is the scientific study of human evolution. Paleoanthropology is a subfield of anthropology, the study of human culture, society, and biology. The field involves an understanding of the similarities and differences between humans and other species in their genes, body form, physiology, and behavior. Paleoanthropologists search for the roots of human physical traits and behavior. They seek to discover how evolution has shaped the potentials, tendencies, and limitations of all people. For many people, paleoanthropology is an exciting scientific field because it investigates the origin, over millions of years, of the universal and defining traits of our species. However, some people find the concept of human evolution troubling because it can seem not to fit with religious and other traditional beliefs about how people, other living things, and the world came to be. Nevertheless, many people have come to reconcile their beliefs with the scientific evidence.

Early human fossils and archeological remains offer the most important clues about this ancient past. These remains include bones, tools and any other evidence (such as footprints, evidence of hearths, or butchery marks on animal bones) left by earlier people. Usually, the remains were buried and preserved naturally. They are then found either on the surface (exposed by rain, rivers, and wind erosion) or by digging in the ground. By studying fossilized bones, scientists learn about the physical appearance of earlier humans and how it changed. Bone size, shape, and markings left by muscles tell us how those predecessors moved around, held tools, and how the size of their brains changed over a long time. Archeological evidence refers to the things earlier people made and the places where scientists find them. By studying this type of evidence, archeologists can understand how early humans made and used tools and lived in their environments.

The process of evolution

The process of evolution involves a series of natural changes that cause species (populations of different organisms) to arise, adapt to the environment, and become extinct. All species or organisms have originated through the process of biological evolution. In animals that reproduce sexually, including humans, the term species refers to a group whose adult members regularly interbreed, resulting in fertile offspring — that is, offspring themselves capable of reproducing. Scientists classify each species with a unique, two-part scientific name. In this system, modern humans are classified as Homo sapiens.

Evolution occurs when there is change in the genetic material — the chemical molecule, DNA — which is inherited from the parents, and especially in the proportions of different genes in a population. Genes represent the segments of DNA that provide the chemical code for producing proteins. Information contained in the DNA can change by a process known as mutation. The way particular genes are expressed – that is, how they influence the body or behavior of an organism — can also change. Genes affect how the body and behavior of an organism develop during its life, and this is why genetically inherited characteristics can influence the likelihood of an organism’s survival and reproduction.

Evolution does not change any single individual. Instead, it changes the inherited means of growth and development that typify a population (a group of individuals of the same species living in a particular habitat). Parents pass adaptive genetic changes to their offspring, and ultimately these changes become common throughout a population. As a result, the offspring inherit those genetic characteristics that enhance their chances of survival and ability to give birth, which may work well until the environment changes. Over time, genetic change can alter a species’ overall way of life, such as what it eats, how it grows, and where it can live. Human evolution took place as new genetic variations in early ancestor populations favored new abilities to adapt to environmental change and so altered the human way of life.

The God Delusion

Have you heard of a beautiful book,written by Richard Dawkin’s ?

Here are some link’s regarding.

To know about the book click here

download the book here

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Quotes from The God Delusion

“The God of the Old Testament is arguably the most unpleasant character in all fiction: jealous and proud of it; a petty, unjust, unforgiving control-freak; a vindictive, bloodthirsty ethnic cleanser; a misogynistic, homophobic, racist, infanticidal, genocidal, filicidal, pestilential, megalomaniacal, sadomasochistic, capriciously malevolent bully.”

-Chapter 2

“I am one of an increasing number of biologists who see religion as a by-product of something else.”

-Chapter 5

“By contrast, what I, as a scientist, believe (for example, evolution) I believe not because of reading a holy book but because I have studied the evidence… Books about evolution are believed because they present overwhelming quantities of mutually buttressed evidence.”

-Chapter 8

“… [Moral absolutism] rules the minds of a great number of people in the world today, most dangerously so in the Muslim world and in the incipient American theocracy… Such absolutism nearly always results from strong religious faith, and it constitutes a major reason for suggesting that religion can be a force for evil in the world.”

-Chapter 8

Why Water?

We all know that water is good for us, but often the reasons are a little fuzzy. And even if we know why we should drink water, it’s not a habit that many people form.

But there are some very powerful reasons to drink lots of water every day, and forming the habit isn’t hard, with a little focus.

The thing about it is, we don’t often focus on this habit. We end up drinking coffee, and lots of soda, and alcohol, not to mention fruit juices and teas and milk and a bunch of other possibilities. Or just as often, we don’t drink enough fluids, and we become dehydrated — and that isn’t good for our health.

I’ve made drinking water a daily habit, although I will admit that a couple of years ago I was more likely to drink anything but water. Now I don’t drink anything but water, except for a cup of coffee in the morning and once in awhile a beer with dinner. I love it.

Here are 9 powerful reasons to drink water (with tips on how to form the water habit afterwards):
Weight loss
Water is one of the best tools for weight loss, first of all because it often replaces high-calorie drinks like soda and juice and alcohol with a drink that doesn’t have any calories. But it’s also a great appetite suppressant, and often when we think we’re hungry, we’re actually just thirsty. Water has no fat, no calories, no carbs, no sugar. Drink plenty to help your weight-loss regimen.

Heart healthy
Drinking a good amount of water could lower your risks of a heart attack. A six-year study published in the May 1, 2002 American Journal of Epidemiology found that those who drink more than 5 glasses of water a day were 41% less likely to die from a heart attack during the study period than those who drank less than two glasses.

Energy
Being dehydrated can sap your energy and make you feel tired — even mild dehydration of as little as 1 or 2 percent of your body weight. If you’re thirsty, you’re already dehydrated — and this can lead to fatigue, muscle weakness, dizziness and other symptoms.

Headache cure
Another symptom of dehydration is headaches. In fact, often when we have headaches it’s simply a matter of not drinking enough water. There are lots of other causes of headaches of course, but dehydration is a common one.

Healthy skin
Drinking water can clear up your skin and people often report a healthy glow after drinking water. It won’t happen overnight, of course, but just a week of drinking a healthy amount of water can have good effects on your skin.

Digestive problems
Our digestive systems need a good amount of water to digest food properly. Often water can help cure stomach acid problems, and water along with fiber can cure constipation (often a result of dehydration).

Cleansing
Water is used by the body to help flush out toxins and waste products from the body.

Cancer risk
Related to the digestive system item above, drinking a healthy amount of water has also been found to reduce the risk of colon cancer by 45%. Drinking lots of water can also reduce the risk of bladder cancer by 50% and potentially reduce the risk of breast cancer.

Better exerciseBeing dehydrated can severely hamper your athletic activities, slowing you down and making it harder to lift weights. Exercise requires additional water, so be sure to hydrate before, during and after exercise.

Unrequited love is bad for your heart

During an average lifetime, the human heart will beat a maximum of 2.5 billion times, says UW-Madison cardiovascular physiologist Richard Moss. Does that mean that falling in love — an activity that increases the rate at which the heart beats — could shorten your life?

Only if it’s unrequited, jokes Moss during his annual Valentine’s Day lecture to first-year medical students.

“When people fall in love,” he explains, “their heart rate increases. Sometimes their hearts even skip a beat.” Even then the math suggests that the heart in love would tick faster, using up its lifetime of beats more quickly.

But, as Moss points out, the symptoms of falling in love are different than those of actually being in love.

“Being in love has a calming effect. After people fall in love and are in love, their resting heart rates tend to be much lower,” he says. Plus, studies show that couples involved in lasting, loving relationships live longer than those who aren’t.

As for heart health, Moss says, “it’s much better to fall in love and stay in love than to never fall in love at all.” But, he does mention that the most dangerous type of love is unrequited: “These people keep falling in love but don’t experience the long-term benefits of being in love.”

For evidence about love’s benefits, Moss turns to animals that seem especially well designed for amour (for the purpose of procreation). The oyster toadfish, for example, has a sonic muscle that vibrates nearly 200 times per second. This rapid vibration, Moss says, produces an alluring song that attracts mates.

Unlike the oyster toadfish, which spends its life on the ocean floor and has the time to attract a mate, many people are too busy for heart-racing romance. For these people, Moss recommends chocolate — a treat, he says, that can produce some of the same symptoms as falling for someone. Every year during the lecture, he offers chocolate hearts to his students, many of whom admit they have time only to study.

Although Moss says the annual lecture is primarily meant to be fun and alleviate his students’ stress at mid-term, he does say that it conveys important physiological lessons about “the salubrious effects of falling in love and the many animals that make love part of their lives.”

Moss, being the “hearty” guy he is, says, “Valentine’s Day is a high holiday. It’s the best day of my year!”