Telling the arthropod tale of life

They had sifted through the forest floor’s leaves and dirt for days, looking for a tiny type of daddy longlegs native to New Zealand, but had little more than dirty hands to show for it.

Gonzalo Giribet, a professor of organismic and evolutionary biology, managed to remain upbeat, but with each passing day the sick feeling in doctoral student Sarah Boyer’s stomach grew. The two had traveled halfway around the world looking for the daddy longlegs as part of Boyer’s dissertation.

No daddy longlegs, no dissertation.

“We were trying to collect from many different localities and coming up with nothing,” Boyer recalled. “Nothing, nothing, nothing.”

But Giribet, who served as Boyer’s doctoral adviser, wasn’t fazed. His conviction that they would eventually find what Boyer needed and his delight and enthusiasm for what they did find — whether it applied to her research or not — buoyed her spirits.

Those who know Giribet will tell you Boyer’s experience is not unusual. Giribet is not only a respected scientist, he genuinely loves his work. Even to a visitor speaking with him in his Biological Laboratories office, Giribet’s continued passion for what started as a beachcomber’s shell collecting is apparent.

“It’s something I’ve been doing since I was a kid,” Giribet said. “As a kid you’re collecting pretty shells, then you understand evolution and diversity. You get to pick the organisms that you really like to answer questions of fundamental interest about evolutionary biology. Then you visit different places to see those organisms. It’s the perfect combination. How can we not love it?”

A globally recognized expert in arthropods, it’s a good thing Giribet is energetic. Arthropods are an enormous group of creatures, encompassing 85 percent of all species on Earth, including insects, spiders, centipedes, snails, and crustaceans. Giribet once said during a lecture that if an alien landed anywhere on earth, the chances are pretty good the first earthling it would meet would be an arthropod. Giribet has done research on such a wide variety of species that he’s sometimes asked which Giribet he is: the one who works on mollusks or the one who works on harvestmen.

He’s both.

“I work on many different groups and questions because I’m interested in many things about animal diversity,” Giribet said.

Giribet’s work takes him to a host of different environments around the world. Since arthropods are found everywhere from the ocean bed to the forest floor, so is Giribet.

Named a professor of organismic and evolutionary biology in January, Giribet, 37, dives in the ocean as well as he digs around in the fallen leaves, and sometimes takes his students with him. He teaches a field class in the Bahamas and Panama during which students snorkel to learn about marine invertebrates. On sabbatical this year, he’s planning a trip in December to the ocean off San Diego to collect deep sea marine mollusks and has plans in the coming months to visit Sicily, Sardinia, Morocco, and Cameroon.

Giribet’s fascination with arthropods was born of his love of the outdoors. The son of a legal administrator and an engineer who tended nuclear power plants — “like Homer Simpson,” he joked — Giribet grew up in the small Spanish town Vilanova i la Geltrú, on the Mediterranean coast 50 kilometers south of Barcelona.

As a boy, Giribet spent time windsurfing and beachcombing, gathering interesting shells for a collection he maintains today — and occasionally uses in his work. Giribet still windsurfs whenever he can, heading to Cape Cod on free weekends. He describes it as a way to recharge himself so he can dive back into his work refreshed. He windsurfs well enough to place seventh in last summer’s world championships in the waters off his native Spain. He sailed in regatta-style races 12 times in seven days, placing seventh in his class, a showing he blamed on his lack of training and on blistered hands from gripping the boom.

“My hands got worse and worse, day after day,” Giribet said. “I hadn’t raced in 10 years. I want to train next year and do much better.”

In college, Giribet pursued a dual concentration while an undergraduate at the University of Barcelona, studying both zoology and fundamental biology. He received his bachelor’s degree in 1993 and his doctorate, also from the University of Barcelona, in 1997. He came to the United States then for a fellowship at the American Museum of Natural History in New York, working with Curator of Invertebrate Zoology Ward Wheeler. Giribet came to Harvard in 2000 as an assistant professor and has been at the University since.

Wheeler, who has collaborated with Giribet on several projects and publications, described him as an engaging guy and a pretty decent cook to boot. Giribet, Wheeler said, is not only a good scientist, he’s an excellent colleague and generous with his work, sharing not just the workload, but the credit as well. He’s also a good scientific manager, Wheeler said.

The latter skill has come in handy, particularly in recent years. Giribet is the primary investigator for international collaborations under the National Science Foundation’s (NSF) Assembling the Tree of Life program. The program seeks to take advantage of the recent burst of scientific information brought on by improving technology to update what’s known about the relationships between living things.

Giribet has been working for several years on the tree of the protostomes, a group of nonvertebrate animals that encompass more than a million of the 1.7 million named species on earth, including insects, mollusks, and flatworms.

The project, a collaboration between the Harvard Museum of Natural History, the American Museum of Natural History, the Kewalo Marine Lab in Hawaii, the Scripps Institution of Oceanography, and natural history museums in London and Denmark, seeks to use all available information on existing and extinct animals to update our understanding of protostome origin and evolution over the past 540 million years.

More recently, Giribet took on a second Tree of Life project, finding out in September that he had received an NSF grant to construct the Tree of Life of bivalves, including clams, mussels, and oysters. The project, to be conducted by an international team of researchers, will explore bivalves’ evolutionary relationships through both morphology and DNA data.

But Giribet doesn’t just look at the relationships between arthropod species, he also mines that information for what it can tell us about the early Earth. He is using the daddy longlegs he was looking for with Boyer, which have the tongue-twisting name Cyphophthalmi, as a window through which to view the Earth more than a hundred million years ago.

The tiny, short-legged Cyphophthalmi are related to the round-bodied, long-legged arachnid that is familiar to many as a daddy longlegs. Many seeing them for the first time wouldn’t guess the two were related, though as Boyer discovered, seeing them for the first time takes some doing. Not only are they tiny — just millimeters across — and living on the forest floor, they’re also well-camouflaged. Cyphophthalmi have two important traits, however, that, to Giribet at least, makes them worth the effort: They’re old and they stay put.

Scientists have tried before to use the relationships between similar species of animals that live in different places to figure out what the world looked like when their common ancestors emerged. The problem, however, is that most global species have become global because they travel — they fly or run or float or drift from place to place. So although the relationships between species can be determined, it is hard to figure out where on Earth the ancestral species lived.

It’s different with Cyphophthalmi. Their tiny size and the fact that they live in the dirt means they don’t move around much. In fact, Giribet believes the different groups of Cyphophthalmi have stayed put even as the continents have moved under them.

That allows Giribet to examine the relationships between different Cyphophthalmi species and draw conclusions about how the Earth’s continents once fit together.

In research published last summer in the Journal of Biogeography, Giribet, Boyer, and colleagues confirmed that Florida was once part of Africa, breaking off when North America pulled away from the supercontinent Gondwana. The group’s results show that species of Cyphophthalmi living at the world’s southern tips — the southernmost parts of Africa, South America, Australia, and New Zealand — are all related even though they’re separated by thousands of miles of ocean today. Similarly, species in North America and Europe also appear to be related, as do those in Florida, northern South America, and central Africa.

Those conclusions, of course, came after years of hard work, both in the field and in the lab. Department of Organismic and Evolutionary Biology Chair Andrew Biewener said that a hallmark of Giribet’s work is that he investigates not just the evolutionary relationships of the creatures he studies, but also their natural history and relationship to their environment.

“There are few in the world with his breadth of knowledge of invertebrates and factors that have influenced their biodiversity,” Biewener said. “His work will be central for future work that seeks to assess biodiversity and how global climate change or other biotic and abiotic factors are likely to affect the biodiversity of invertebrate animals.”

Giribet’s influence on the future extends beyond scientific knowledge, however. Boyer, who did eventually find the daddy longlegs she sought, graduated last spring and is now an assistant professor at Macalester College. Not only did Giribet teach her about arthropods, she said, he influenced how she interacts with her students.

“We’re partners in the research,” Boyer said. “I try to follow his model and be very positive. There’s always a way out of every predicament.”