Where do rainbows come from, Daddy?

What about flying cars—and LSD?

In the beginning, there was always the toddler's query, which led to the schoolchild's raised hand and, still later, the engineer's back-of-the envelope sketch of a new invention.

Everything started somewhere—and someone had to ask. Think of what you are about to read as a collection of queries rooted in childlike curiosity about the world around us and the still larger universe that stretches beyond.

After exploring the big questions in the articles that precede this section—the origins of the universe and the beginnings of life itself—we now turn to everything else. The origins of external ears, Scotch tape, the ethereal evolution of love and even artificial hearts are revealed in the pages that follow.

Of course, many of you were wondering what came before the big bang. But others ponder an even more urgent question. Read on, and you may find out who or what prevailed in the contest between the chicken and the ovum. —The Editors

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The simple magic of their shape and colors still puzzles

Flying Car
A long-standing dream

Large brains may have led to the evolution of amour

Digital Audio Player
Mobile music rocked the record industry

The small fry of the solar system have troubled pasts

Their inventor may not have known how they actually work

External Ears
They guide sound to the sensitive middle ear

Its probability-based view of misfortunes helped to shape the scientific outlook

Scotch Tape
Most new inventions quickly fall into oblivion; some stick

These wonder-drug molecules might have evolvedto help bacteria speak with their neighbors, not kill them

Artificial Heart
Did the wrong man get credit for the world’s first permanent pump?

Coriolis Effect
The earth’s spin influences hurricanes but not toilets

Ball Bearings
Cheap steel was key to allowing the routine design of parts that rolled against one another

They long predate the smile

The answer to the age-old riddle is biologically obvious

When a cell’s controls break down, chaos is unleashed

The Stirrup
Invention of the stirrup may rival that of the longbow and gunpowder

An inquisitive Swiss chemist sent himself on the first acid trip

Preparing foods with fire may have made us humans what we are

Their origin is one of the deepest questions in modern physics

Legs, Feet and Toes
The essential parts for walking on land evolved in water

Paper Money
A substitute for coins turned into a passport for globalization

The Vibrator
One of the first electrical appliances made its way into the home as a purported medical device

Buckyballs and Nanotubes
A once overlooked form of carbon may represent the future of technology

Economic Thinking
Even apparently irrational human choices can make sense in terms of our inner logic

Synonymous with life, it was born in the heart of stars

The Placenta
An eggshell membrane evolved into the organ that lets fetuses grow in the womb

Graphical Perspective
“Realistic” imagery depends on relatively recent cultural assumptions and technical skills

The Paper Clip
Despite its shortcomings, the iconic design will likely stick around

Solving the riddle of its lethal contagion modernized the understanding of disease

Intermittent Windshield Wipers
A now routine automotive feature pitted an individual inventor against the entire industry

The Eye
What was half an eye good for? Quite a lot, actually

Its hardness is natural; its value is not

The Pill
Infertility treatments led to reproductive liberation

The Mechanincal Loom
Programmable textile machinery provided inspirationfor the player piano and the early computer

Mad Cow Disease
Cannibalism takes its revenge on modern farms

The reaction that makes the world green is just one of many variants

The Blueprint
A failure for photography, it was long irreplaceable for duplicating house plans

Barbs became plumes long before birds took wing—in fact, long before birds

Structure, strength and storage in one package


Religious Thought
Belief in the supernatural may have emerged from the most basic components of human cognition

Recorded Music
The first recordings remained silent for 150 years

The Color Blue
The natural pigment was once a “precious” color

Facial Expressions
Our unique expressiveness may have a three-million-year-old pedigree

Gamma Rays
To create one typically means you have to destroy something, be it a single particle or an entire star

It emerged not with a quick flip of the switch but with a slow breaking of the dawn

Mixing the bitter treat with milk was the popular breakthrough

Internal-Combustion Engine
Still powering the world’s vehicle fleet 130 years on

The yummy baked good is one of America’s first and finest contributions to world cuisine

Not needed, but not useless

The Web
The global information resource spun out of research into fundamental physics

Tectonic Plates
The long, strange trip of continental drift

Note: This article was originally printed with the title, "Origins."