We can look high or we can look low in books or in journals, but the result is the same. The scientific literature has no answers to the question of the origin of the immune system.

Thus it seemed to Haeckel that such simple life could easily be produced from inanimate material.

Despite some remaining puzzles, there's no reason to doubt that Darwin had this point right, that all creatures on earth are biological relatives

The basic structure of proteins is quite simple: they are formed by hooking together in a chain discrete subunits called amino acids.

In the 19th century the anatomy of the eye was known in great detail and the sophisticated mechanisms it employs to deliver an accurate picture of the outside world astounded everyone who was familiar with them.

Proteins are the machinery of living tissue that builds the structures and carries out the chemical reactions necessary for life.

It was a shock to people of the nineteenth century when they discovered, from observations science had made, that many features of the biological world could be ascribed to the elegant principle of natural selection.