Human evolution is characterised by a number of important morphological, developmental, physiological and behavioural changes, which have taken place since the split between the last common ancestor of humans and chimpanzees. The first major morphological change was the evolution of a bipedal locomotor adaptation from an arboreal or semi-arboreal one, with all its attendant adaptations, such as a valgus knee, low intermembral index , and reduced upper-body strength.
Later, ancestral humans developed a much larger brain – typically 1,400 cm³ in modern humans, over twice the size of that of a chimpanzee or gorilla. The pattern of human postnatal brain growth differs from that of other apes (heterochrony), and allows for extended periods of social learning and language acquisition in juvenile humans. Physical anthropologistsargue that the differences between the structure of human brains and those of other apes are even more significant than their differences in size.
Other significant morphological changes included the evolution of a power and precision grip, a reduced masticatory system, a reduction of the canine tooth, and the descent of the larynx and hyoid bone, making speech possible. An important physiological change in humans was the evolution of hidden oestrus, or concealed ovulation, which may have coincided with the evolution of important behavioural changes, such as pair bonding. Another significant behavioural change was the development of material culture, with human-made objects becoming increasingly common and diversified over time. The relationship between all these changes is the subject of ongoing debate
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Monday, August 2, 2010
Bee
I wish I was a bee. Bees play an important role in pollinating flowering plants, and are the major type of pollinator in ecosystems that contain flowering plants. Bees either focus on gathering nectar or on gathering pollen depending on demand, especially in social species. Bees gathering nectar may accomplish pollination, but bees that are deliberately gathering pollen are more efficient pollinators. It is estimated that one third of the human food supply depends on insect pollination.Also ,we depend on bees every much !!!!!!!!!!!!!!
Facebook is a social networking website launched in February 2004 that is operated and privately owned by Facebook, Inc, with more than 500 millionactive users in July 2010.Facebook is a social networking website launched in February 2004 that is operated and privately owned by Facebook, Inc, with more than 500 million active users in July 2010.The original concept for Facebook was borrowed from a product produced by Zuckerberg's prep school Phillips Exeter Academy, which for decades published and distributed a printed manual of all students and faculty, unofficially called the "face book". The website currently has more than 500 million active users worldwide.[7]Facebook settled a lawsuit regarding claims over source code and intellectual property.[14] The site has also been involved in controversy over the sale of fans and friends.[15]
Respect
Respect denotes both a positive feeling of esteem for a person or other entity , and also specific actions and conduct representative of that esteem. Respect can be a specific feeling of regard for the actual qualities of the one respected .It can also be conduct in accord with a specific ethic of respect.
How do scientists clone animals?
By a process called somatic cell nuclear transfer.Scientists take a somatic cell from an adult animal and isolate the nucleus from that cell.They then take an egg from another one of the same animal and remove the nucleus from that egg, replacing it with the somatic cell nucleus. They then "fool" the egg into thinking it has been fertilised , and the egg divides and develops as any normal egg would.This fertilised egg is implanted into a fertile female , and it develops as normal.
Monday, March 22, 2010
Internet vs Censorship
No,it should not be censored!The Internet is a global system of interconnected computer networks which is use to serve billions of users worldwide.The Internet carries a vast array of information resources and services, the infrastructure to support electronic mail.It accelerates the creation of new forms of human interactions through communication platform.It has been a major contributor in establishing authentic systems of free trade.The Internet is arguably the most efficient platform in every range of possibities in every aspect. Connecting people from over the world. It has been a major contributor in establishing authentic systems of free trade.
Lionfish
From this article,the sighting of lionfish in atiantic waters were ten years ago.But today,scientists have reported finding more than 400 lionfish per hectare.they have been spotted as far north as massachusetts and as south as mexico and panama.their population increased rapidly due to 'Hurricanes Andrew' which may have smashed one private aquarium thus lionfish into Biscayne Bay and eat and reproduce.Another reason lionfish were released by owners after founding out large appetite.They can colonised rapidly as they do not seem to have any local predators,due to their lionfish stings.To control the population,eat it.They are safe for consumption after removing the needle-like spines.And after cooking,the fish is flaky,almost sweet,like grouper.
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