I wonder if you've heard of Marie Tharp. I hope you have, but suspect you haven't. Even in scientific circles, her name is not exactly a household word.
It should be.
Back in 1912, a German geologist and climatologist named Alfred Wegener noticed correspondences that seemed too great to be coincidences. First, there was the thing that just about everyone wonders about in grade school -- the puzzle-piece contours of Europe and Africa with North and South America. Then there was the fact that the fossil record of those two regions are similar until about two hundred million years ago, and afterward gradually diverge. And last, he observed that the Appalachian, Pennine, and Scandinavian Mountains are geologically similar and seem to have formed at around the same time. As you undoubtedly know, Wegener put all that together and proposed that they were all explained by continental drift -- that the land masses were all united at one point, then broke up and drifted apart, splitting what had been a single continent with a contiguous mountain range into widely-separated pieces.
The main reason this wasn't well-received was not only, or even mainly, because of hidebound scientists clinging to old models; it was that Wegener couldn't explain how, or why, it had occurred. He proposed no mechanism to account for continents "drifting" in what appeared to be solid rock. So while it's a pity for poor Wegener that he'd landed on the correct answer and got no recognition for it (he died at age fifty in 1930 on an expedition to Greenland, thirty years before plate tectonics was proposed), his theory's poor reception is honestly understandable.
What happened to Marie Tharp in the 1950s is less forgivable.
Tharp was an oceanographer who fell into the profession almost by accident. She was fascinated with science, but women back then were actively discouraged from pursuing careers in scientific fields; they were frequently given helpful advice like "it's extremely difficult for women to compete as scientists," with few of the (male) advisors and supervisors asking themselves the question of why that was, and more importantly, if maybe, just maybe, it was a problem they should work on fixing. During World War II, though, when a lot of college-age men were overseas fighting, colleges started actively recruiting -- well, just about anyone, even those from groups that had been previously excluded. Tharp took a geology class and was fascinated by the subject, so she enrolled in graduate school at the University of Michigan at Ann Arbor, completing a master's degree in petroleum geology in 1944.
After that, though, she ran into the difficulty that geology and related sciences rely on field work, and nearly all of the companies that hired geologists didn't allow women to work in the field. So Tharp was relegated to analyzing data -- especially mapping data -- that had been collected and brought back by her male colleagues.
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It was when she was working on a project to map the deep parts of the Atlantic she noticed something odd. For a decade, ships had been crisscrossing the Atlantic Ocean using sounding devices to map the topography of the ocean floor, initially as a way of locating downed aircraft and ships. But as she was creating contour maps, Tharp found that there was a huge mountain range running all the way down the center, from north to south -- and that mountain range had a narrow, deep, v-shaped valley right down the middle. Then she started plotting the epicenters of submarine earthquakes onto the map, and found they coincided almost perfectly with the ridge and valley.
As soon as she saw this, she knew Wegener had been right.
The rift, she claimed, was where the motive force arose that was forcing the continents apart. It was seismically active, and (she rightly predicted) should be characterized by newly-formed igneous rock, as the split between the continents widened and lava from the mantle bubbled up and froze on contact with cold seawater. She told her supervisor, geologist Bruce Heezen, who promptly laughed at her, characterizing her explanation as "girls' talk."
Tharp, fortunately, was not so easily dissuaded. She kept at it, and after several years had enough data amassed that the evidence was absolutely incontrovertible. Even Heezen finally gave in. Those ridges and valleys were eventually found to be a network of rifts encircling the globe like the stitching on a baseball, and her idea that they were responsible for plate tectonics was absolutely spot-on. But it's significant that of the many papers about the Mid-Atlantic Ridge and plate tectonics that Heezen and others published in the 1960s and 1970s, Tharp's contributions were acknowledged on exactly zero of them. The person who was credited with discovering the Mid-Atlantic Rift Zone, and proposing its role in continental drift, was...
... you guessed it...
... Bruce Heezen.
She was eventually recognized for her brilliance and hard work, but like a lot of women scientists, didn't receive it until quite late in her career. She was awarded the National Geographic Society's Hubbard Medal in 1978, Woods Hole Oceanographic Institute's Mary Sears Woman Pioneer in Oceanography Award in 1999, and the Lamont-Doherty Earth Observatory Heritage Award in 2001, five years before her death at the age of 86.
It's certainly easier for women in science now, in part due to indomitable women like Marie Tharp. But the fact that it's not equally easy for men and women -- which it still very much isn't -- illustrates that we have a long way to go in welcoming women, minorities, and LGBTQ+ people into every career avenue. If you're one of those people who has ridiculed DEI (diversity, equity, and inclusion) drives in education, business, and industry, then maybe you should be working harder to create a world where we don't need them any more.
Odd how those who are most vocally against DEI seldom have any cogent arguments why they think it's appropriate or fair to set up roadblocks that result in wasting over half of the potential talent, drive, passion, and genius we have at our fingertips.
Most people who are interested in geology have heard of Wegener, and pioneers like Drummond Matthews, Frederick Vine, and Harry Hess. Far fewer have heard of Marie Tharp, who overcame tremendous personal and professional hurdles to revolutionize our understanding of how the Earth's geological systems work.
Hearing about her struggles won't undo the unfairness and misogyny she dealt with during her entire professional life, but maybe it will assure that this generation of women scientists don't have to endure the same thing.
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Geologists in Wegener's day were, in fact, caught in hidebound ideas, in the same sense that physicists before Einstein were trapped by the notion that time was universally the same. That idea was the unitary notion of the liquid phase. Seismic surveys had very clearly demonstrated (via transmission of transverse seismic waves) that the hot pressurized rock of the mantle is a solid. But that finding actually was demonstrated specifically for short time frames. It turns out that the mantle is a liquid over very long time frames, and supports very slow convection currents.
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