Posts tagged evolution
Posts tagged evolution
Definitely justifiable logic, guys.
- Carl Sagan
Two of science’s luminaries converse on the beauty of science. Neil deGrasse Tyson, astrophysicist and host of NOVA and evolutionary biologist Richard Dawkins will explore the wonders of the Cosmos and of Life, its origins, its inspirations, and why science is not just an option, it is the only reality we possess.
This is one of the best things that I have ever seen.
From The Genius of Charles Darwin Uncut Interviews.
Atheism vs. Stupidism.
All life is related
And it enables us to construct with confidence
The complex tree that represents the history of life
Our planet, the Earth, is as far as we know
Unique in the universe; it contains life
Here plants and animals proliferate in such numbers
That we still have not even named all the different species
Darwin’s great insight revolutionized the way in which we see the world
We now understand why there are so many different species
Every cell is a triumph of natural selection
And we’re made of trillions of cells (Within us is a little universe)
Those are some of the things that molecules do
Given four billions years of evolution (We are, each of us, a multitude)
Now how did the molecules of life arise?
It began in the sea
Some 3 thousand million years ago
Complex chemical molecules began to clump together
These were the “seeds”
From which the tree of life developed
They were able to split, replicating themselves
As bacteria do
The secrets of evolution
Are time and death
There’s an unbroken thread that stretches
From those first cells to us
There isn’t a sharp line dividing humans
from the rest of the animal kingdom
It’s a very wuzzie line
It’s a very wuzzie line,
and it’s getting wuzzier
All the time
We find animals doing things that we,
In our arrogance,
Used to think was “just human”
Its continued survival now rests in our hands
Welcome. And congratulations. I am delighted that you could make it. Getting here wasn’t easy, I know. In fact I suspect it was a little tougher than you realize.
To begin with , for you to be here now trillions of drifting atoms had somehow to assemble in an intricate and intriguingly obliging manner to create you. Its an arrangement so specialized and particular that it has never been tried before and will only exist this once. For the next many years (we hope) these tiny particles will uncomplainingly engage in all the billions of deft, cooperative efforts necessary to keep you intact and let you experience the supremely agreeable but generally unappreciated state known as existence.
Not only have you been lucky enough to be attached since time immemorial to a favoured evolutionary line, but you have also been extremely-make that miraculously-fortunate in your personal ancestry. Consider the fact that for 3.8 billion years, a period of time older than the earths mountains and rivers and oceans, every one of your forebears on both sides has been attractive enough to find a mate, healthy enough to reproduce, and sufficiently blessed by fate and circumstance to live long enough to do so. Not one of your pertinent ancestors was squashed, devoured, drowned, starved, stranded, stuck fast, untimely wounded, or otherwise deflected from its life’s quest of delivering a tiny change of genetic material to the right partner at the right moment in order to perpetuate the only possible sequence of hereditary combinations that could result - eventually, astoundingly, and all too briefly - in YOU.
A Short History of Nearly Everything - Bill Bryson
04 May 2011 by Michael Marshall
WERE asteroids the factories that created life’s building blocks? For the first time, rocks from an asteroid have been shown to power the synthesis of life’s essential chemicals.
The asteroid in question fell to Earth on 28 September 1969, landing on the outskirts of the village of Murchison in Victoria, Australia. Tests showed it was laced with amino acids and some of the chemicals found in our genetic material.
The discovery suggested that space was not the chemically sterile place it was once thought to be, and that organic chemistry was widespread. It hinted that the molecules life needed to get started could have been produced in space, before dropping to Earth.
But how did those molecules form? Raffaele Saladino of the University of Tuscia in Viterbo, Italy, and colleagues wondered if they could have been made deep inside the asteroids from which some meteorites break off. The team knew that a simple chemical present in space, called formamide, can be transformed into many biomolecules, so they used that as their starting point.
They obtained 1 gram of the Murchison meteorite, ground it to powder and removed all the organic molecules, leaving just the mineral. They mixed this with formamide and heated it to 140°C for 48 hours. The reaction produced nucleic acids - essential building blocks of DNA and RNA - as well as the amino acid glycine, carboxylic acids and a precursor to sugar (Origins of Life and Evolution of Biospheres, DOI: 10.1007/s11084-011-9239-0). This suggests the meteorite’s parent asteroid was a chemical factory, Saladino says.
Crucially, the compounds produced are both metabolic and genetic, covering two key parts of primitive life, says Monica Grady of the Open University in Milton Keynes, UK, who was not involved in the study. “If you can catalyse both reactions in the same place, from the same starting material, that’s obviously advantageous.”
The ability to produce a range of essential molecules sets the meteorite mineral apart from Earth minerals, says Mark Sephton of Imperial College London. On Earth, the formation of each biomolecule tends to be catalysed by a different mineral, meaning they end up separated and less likely to form life.
Saladino’s team also found that the meteorite mineral could stabilise RNA, thought by some to have been the first genetic material. RNA reacts with water and breaks down easily. Most minerals accelerate this process, but the team found that the Murchison mineral did not. “If RNA could be synthesised [inside the asteroid], this environment would stabilise it,” Saladino says.
Texas science standards
Two years ago, the Texas State Board of Education voted 13-2 to put in place a plan that would require teachers to encourage students to scrutinize “all sides” of scientific theories, including the theory of evolution.
Critics of the plan argued that it would allow non-scientific ideas such as creationism and intelligent design to slip into Texas classrooms even though the board president at the time, Don McLeroy, had previously said, “Anything taught in science has to have consensus in the science community and intelligent design does not.”
Now, proposed science education materials — all web based — are available for review on the board’s website. The National Center for Science Education and the Texas Freedom Network, organizations that criticized the new plan, reviewed the materials and found their fears confirmed.
Intelligent design teachings