Feature Stories

A 750-million-year-old fossil discovered by geoscientist Phoebe Cohen may hold clues to how life has changed the earth—and vice versa.

Following up on work done by scientists in the 1970s, Cohen and a fellow Harvard University graduate school student traveled to the Yukon in 2007 to study rock formations and found a veritable goldmine of fossil-containing rock. Advancements in scientific tools and instruments in the last 40 years allowed Cohen to examine the fossils in a new way, by dissolving the carbonate rock in acetic acid rather than looking at a sliver or cross-section of the rock, as had been done in the past.

“After the carbonate dissolves away, what’s left is organic matter,” says Cohen, now an assistant professor in the Geosciences Department. And what she was able to see in the organic matter amazed her: three-dimensional “bones” of what might be one of the earth’s first eukaryotic single-celled organisms to make hard parts.

Eukaryotic cells have a nucleus and organelles, like animal and plant cells but unlike bacteria cells. The fossil Cohen discovered, which she named Quadrireticulum palmaspinosum (loosely translating to “four-sided net with palm tree spine”), measures about one-tenth the width of a human hair.

Why did a creature so tiny need bones? Cohen’s theory is that at a certain point in history, single-celled organisms needed to “biomineralize”—or create a type of exoskeleton—in order to protect themselves from being eaten by other single-celled organisms. Later, these biomineralized organisms, weighed down by their hard parts, sank to the bottom of the ocean.

As the organisms became buried in sediment, the carbon they contained was locked away with them, reducing the levels of carbon in the ocean and the atmosphere. Over the next 750 million years they developed into the giant rock in the Yukon that Cohen studied. The process may have caused the earth to cool, perhaps eventually contributing to what Cohen and other scientists call “a snowball earth event,” when ice covered the entire planet for millions of years.

With the help of research assistants Nakita VanBiene ’15, who is a geoscienes major, and Kim Kiplagat ’16, Cohen is now studying snowball earth events. She’s in the process of writing a grant proposal to research the time periods before, during, and just after the two major snowball earth events in our planet’s history, which took place 717 million and 635 million years ago, to better understand the relationships between evolutionary events such as biomineralization and events in the earth system such as climate change.

“This work helps us understand how life has evolved through time, in response to both other living things and to the environment,” Cohen says. “We are working toward a better understanding of the dynamics between evolution and changes in the earth’s climate over geologic time scales.”

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In this cradle of intellectual exploration, transgender people at Williams are on that most basic human quest—figuring out who they are. Illustration by Cathy Gendron.

College is a chrysalis into which 3 million hopeful young freshmen enter each fall. Four years later, most emerge smarter, surer, more worldly—ready to spread their wings.

For some students, the metamorphosis is far more significant, and more fundamental, than deciding whether to major in anthropology or astrophysics.

They start college as one gender. They leave as another.

No one knows exactly what portion of the population is born feeling out of sync with their assigned sex. By any measure, the number at Williams is small. But so is the college. And for students making decisions about how they will present themselves to peers and strangers alike, Williams’ close-knit community can be intimidating even as it is comforting. While most people yearn for acceptance, trans people are also coming to accept themselves. And for some the only way to do that is to switch to the gender they feel they were meant to be.

This self-discovery complicates every aspect of campus life, from the gender boxes prospective students must select on their college applications to the names printed on graduating seniors’ diplomas. In between, they worry about housing assignments, physical education classes, and which bathrooms to use. They wonder if they’ll be able to find friends who support them, if they’ll find doctors and therapists if they need them, and if they’ll be able to pay the doctors if insurance won’t.

“Personal transitions are like wooden Russian dolls,” says Norman Spack ’65, an endocrinologist who has done pioneering work with transgender youth through Boston Children’s Hospital (work for which he received a Bicentennial Medal from the college in September). “Open the outermost, and there’s another within. It’s equally shiny, often different, and hopefully pleasing to the eye.”

Read more of this story in the fall 2012 issue of Williams Magazine.

Bicentennial Medalist Charlie Waigi ’72 during convocation. Photo by Erna Grasz

In September, Charles N. Waigi ’72 received a Williams Bicentennial Medal for distinguished achievement. It was only his second visit to campus since his graduation 40 years ago. He’d been on the college’s list of “lost” alumni since 1979, around the time he left the U.S. for his native Kenya. But his classmates tracked him down in 2007, hoping to convince him to attend their 35th reunion.

Retired after a 24-year career with a Kenyan development financial institution, Waigi had already begun a new chapter in his life—running the Jeremy Academy with his wife, Teresia. Initially using Waigi’s pension funds and operating out of their living room with just one student, the Jeremy Academy has since grown to serve nearly 500 children in nursery school through eighth grade.

When Waigi returned to Williams for his 35th reunion, he joked with classmates, “I didn’t know I was lost.” To learn where he’s been, read an excerpt from his Bicentennial Medals talk, published in the fall 2012 Williams Magazine.

View Waigi’s remarks to Williams students.