C4 Photosynthesis


Supercharged plants
32-25 million years ago

Plants have been busily harnessing sunlight to make sugar for hundreds of millions of years – a process called photosynthesis. But fairly recently, some plants have found a better way to do it. C4 photosynthesis is far more efficient than normal photosynthesis, allowing C4 plants to cope with harsh conditions. Today scientists are trying to engineer rice to use C4 photosynthesis, to help feed the growing population.

See other: History of Life

On Stars in Space


“Put three grains of sand inside a vast cathedral, and it will be more closely packed with sand than space is with stars.”

– James Jeans

Conversations: Civilization of Ignorance


Sappho
All complex life on earth has developed from simpler life forms over billions of years. This is a fact that no longer admits of intelligent dispute. If you doubt that human beings evolved from prior species, you may as well doubt that the sun is a star.

Galene
Well, not to be facetious, but the sun doesn’t look like any other star.

Sappho
Granted, the sun doesn’t seem like an ordinary star, but we know that it is a star that just happens to be relatively close to the earth.

Helena
The point is this: imagine your potential for embarrassment if your religious faith rested on the presumption that the sun was not a star at all. Imagine millions of Christians in the United States spending hundreds of millions of dollars each year to battle the godless astronomers and astrophysicists on this point. Imagine them working passionately to get their unfounded notions about the sun taught in our nation’s schools. This is exactly the situation Christians are now in with respect to evolution. Continue reading

The Power of Sunlight


Photosynthesis
3.4 billion years ago

All life needs energy to survive, and the biggest source of energy for life on Earth is the Sun. Some of the early micro-organisms evolved a way to use the energy from sunlight to make sugars out of simpler molecules. This process is called photosynthesis. But unlike green plants today, the first photosynthesising organisms did not release oxygen as a waste product, so there was no oxygen in the air.

See other: History of Life

Earth is Born


Birth of a planet
4.5 billion years ago

Earth grew from a cloud of dust and rocks surrounding the young Sun. Earth formed when some of these rocks collided. Eventually they were massive enough to attract other rocks with the force of gravity, and vacuumed up all the nearby junk, becoming the Earth. The Moon probably formed soon after, when a planet-sized chunk of rock smashed into the Earth and threw up a huge cloud of debris. This condensed into the Moon.

See other: History of Life

Planetesimal [Noun.]


Baby planet; that is to say, a solid object (larger than approximately 1 km in the solar nebula – the birthplace of a star) arising during the accumulation of planets whose internal strength is dominated by self-gravity and whose orbital dynamics is not significantly affected by gas drag.

Bald All Over


No more body hair
3.3 million years ago

Humans are the nearly-hairless apes. No one knows why, but it happened 3-4 million years ago. That’s when pubic lice evolved, which could only infest us once our other body hair was gone. Exposed to the Sun, our skin darkened. From then on all our ancestors were black, until some humans left the tropics.

See other: What Makes Humans Human?