Over time, populations evolve as traits that help them survive are typically selected, and traits that make it harder to survive are usually weeded out.
Connections that are used are kept and strengthened, while under-used ones are weeded away, creating a brain that is both fine-tuned to its environment and energy efficient.
In these notes, Mr Studwell wanders into the weeds of development (quite literally: Japanese rice is weeded nine times a year, he writes).But he never gets lost.
Now there were only the well-bound little-read English Classics, which were weeded out of her father's library to fill up the small book-shelves in the drawing-room.
So a bad gene that tends to kill relatively young adults is also likely to indirectly kill their young kids, and thus be weeded from the gene pool, too.
In the process, the government has weeded out tens of thousands of ghost employees, since the embezzlers who invented them could not open accounts in their names without a matching ID.
While he dug or weeded he whistled or sang bits of Yorkshire moor songs or talked to Soot or Captain or the brothers and sisters he had taught to help him.
She went from place to place, and dug and weeded, and enjoyed herself so immensely that she was led on from bed to bed and into the grass under the trees.
She searched about until she found a rather sharp piece of wood and knelt down and dug and weeded out the weeds and grass until she made nice little clear places around them.