ScienceIQ.com

How Did Dogs Evolve?

While the status of the dog as humankind's best and oldest friend remains unchallenged, debate rages about just how far back the friendship goes. Fossils of domesticated dogs appear in the remains of human settlements between 10,000 and 14,000 years old, but measurements of mutations in the genes of mitochondria (the 'energy factories' of cells) ...

Continue reading...

HowDidDogsEvolve
Biology

Ergot, Witches & Rye. Oh My!

Did you know that a disease of rye is connected to LSD and witches? Ergot is caused by a fungus that attacks a number of cereal grains, but rye is most severely infected. The healthy grains are ... Continue reading

ErgotWitchesRyeOhMy
Biology

What Causes Wrinkles?

Elastin and collagen are proteins in the skin's underlying layers that give it firmness and elasticity. As we age, skin begins to lose its elastin fibers. The fibers start to tangle in disorganized ... Continue reading

WhatCausesWrinkles
Engineering

High Altitude

Have you ever read the directions on a box of cake mix? There are special instructions for high-altitude baking. Has anyone who visited the Rocky Mountains told you how hard it was to breathe there? ... Continue reading

HighAltitude
Mathematics

Perfect Numbers

Some numbers are more special than others. According to Pythagoras (569 BC - 475 BC) and Euclid (325 BC - 265 BC), some are so special that they called them mystical or perfect numbers. The first ... Continue reading

PerfectNumbers

Jumping Starlight

JumpingStarlight'Twinkle, twinkle, little star, how I wonder what you are,' says the song by Jane Taylor. But stars don’t really twinkle; their light reaches the earth in a steady way. Why then do we see them flickering around in the sky? The answer is in the atmosphere.

The air in the atmosphere is turbulent. That means there are different layers of air with different temperatures; some hot, some cooler. Hot air is less dense than cooler air. The light of the stars bends when it goes from a less dense part of the atmosphere to a denser one. Think about a straw in a glass of water. The straw seems to bend when it enters the water, but actually light is bending as it goes from one medium (air) to another (water). This behavior of light is called refraction.

Little packets of air, called cells, move around in the atmosphere. Starlight bends a little each time it goes through one of these cells. When you see a star from the ground, its light has crossed hundreds of cells in the sky, refracting in random directions - so the image of the star appears to jump!