When asked for early geologists, all of us can rattle off names. Some of us may remember Nicolas Steno, the father of stratigraphy. We certainly mention James Hutton (father of deep time) and Charles Lyell (father of modern geology). Some of us would even throw Charles Darwin's name in there for his work on volcanic islands and coral reefs.

Geology has many fathers, and we know them well. But few of us can name its mothers. Mothers who sacrificed far more than most of the men did - many women could only succeed in the geosciences if they remained unmarried and childless (and some organizations, like the British Geological Survey, made that a formal requirement). They fought discrimination and doubt. They worked hard for a fraction of the recognition their male colleagues got. Despite all the decks stacked against them, they made important contributions to our knowledge of the world. Forgetting the women who left us geoscience legacies is intolerable. We need to remember.

This series seeks to restore these women to our lexicon of famous geologists. Along with Charles Lyell, I want you to remember his wife Mary, who worked beside him. When thinking of early contributors to our understanding of the Earth and its past, I want you to remember Etheldred Bennett, who carefully collected some of the first fossils with soft tissues preserved we ever discovered, and found herself a member of the Imperial Natural History Society of Moscow.

There are women on my little list who made foundational discoveries; others who pushed for revolutions in the way we educate our future scientists; many who added one more brick to the foundation of our knowledge. There were women who had to overcome extraordinary obstacles no man faced, women who did their field work in dresses, women who said "I can" when their entire society said "You can't." And they reached down for the women coming up behind them, helped them over the hurdles, said "You can, too."

One thing I've discovered in searching out the forgotten people is that they're worth remembering. They had things to say we would do well to listen to. They were brilliant, insatiably curious, determined, and dogged. They made contributions we take advantage of all these years and centuries later, without realizing that these women made this innovation, this discovery, possible. They had fascinating lives. They're role models, inspirations, people who have queued up and taken their proper place in my pantheon of personal heroes and heroines.

They left the geosciences better than they found them. They cleared the way for all of the brilliant women who work in the geosciences today. Our work toward equality still isn't finished, but we're on our way. And it helps, on this journey, to remember those who traveled the paths ahead of us. Knowing them shows us how far we've come, how far we've yet to go, and gives us a few ideas on how to get there.

All of science is built by standing on the shoulders of giants. I'm glad some of those shoulders will no longer be invisible.