Washington State Magazine

Winter 2011


Winter 2011

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In This Issue...

Features

When Memory Fades :: With memory notebooks and smart apartments that use motion technology to track their residents’ daily behaviors, WSU neuropsychologists are exploring ways to help patients and their families cope with age-related memory loss. Meanwhile, two scientists have discovered a means to restore neural connectivity. by Tim Steury

{ WEB EXCLUSIVE—Video: Smart Apartment Research }

Attention! :: Cell phones, Internet, car horns, children, commercials—all carry information and all work together to create in us what social scientist Herbert Simon calls “a poverty of attention.” How do you rise above the din to capture what is most important? You may be surprised to learn that one of the oldest forms of communication is still one of the best. by Eric Sorensen

{ WEB EXCLUSIVE—Tips: How to focus your attention }

All About Everett :: The blue-collar Snohomish County city just 25 miles north of Seattle recently asked WSU to take over the University Center where graduates of its community college can go on to complete four-year degrees in a variety of disciplines, including engineering. Snohomish, Skagit, and Island counties have been underserved by the state’s four-year programs. by Hannelore Sudermann

{ WEB EXCLUSIVE—Map: Everett: City Snapshots }

Essay

Collegiate athletics in the 21st century :: by Thabiti Lewis

Panoramas

{ WEB EXCLUSIVE—Story: Sabermetrics As Told By The Simpsons }

{ WEB EXCLUSIVE—Recipes: Unifine Flour Cookbook from Leonard Fulton’s Fairfield Milling Co. (PDF, 2.2MB) }

{ WEB EXCLUSIVE—Story: Flourgirls and the WSU-Unifine connection }

{ WEB EXCLUSIVE—Video: A talk with architect Jim Olson}

Departments

:: Sports: John Olerud: Faith, hope, and horses

:: In Season: Wheat: A 10,000-year relationship

:: Last Words: Are our pictures worth a thousand words? (Washington State Magazine 2012 calendar)

{ WEB EXCLUSIVE—Timeline: John Olerud’s baseball career }

{ WEB EXCLUSIVE—Books and videos: Bread }

{ WEB EXCLUSIVE—Calendar: Order your Washington State Magazine 2012 calendar }

Tracking

New Media

:: The Man Who Dammed the Yangtze: A Mathematical Novel by Alex Kuo

:: Building New Pathways to Peace edited by Noriko Kawamura, Yoichiro Murakami, and Shin Chiba

:: Montaña Y Caballo by Yarn Owl - Tyler Armour ’10, Tim Meinig ’10, Ted Powers ’09, and Javier Suarez ’10

:: New & Noteworthy: Standing Above the Crowd by James “Dukes” Donaldson ’79; Eliminate the Chaos at Work by Laura Leist ’91; Pick Up Your Own Brass: Leadership the FBI Way by Kathleen McChesney ’71 and William Gavin; The Itty Bitty Guide to Trees: A Children’s Identification Guide to Trees of the Inland Northwest by Jaclyn Gotch ’07 MED, Lisa Bird, and Amy Ross-Davis; The Alpine Tales by Paul J. Willis ’80 MA, ’85 PhD

Cover photo: William Lipe, PhD, Archaeology, born 1935 — came to Washington State University in 1976. (See First Words.) By Robert Hubner

Panoramas
Donna Holmes. <em>Shelly Hanks</em>

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Donna Holmes. Shelly Hanks

An evolutionary myth is dismissed

by | © Washington State University

Even though a paper on guppy senescence by evolutionary biologist Donna Holmes and her colleagues has circulated for several years, the “grandmother hypothesis” still persists.

And understandably so. One of those rare feel-good stories from evolutionary theory, the grandmother hypothesis attempts to explain menopause in humans as an evolutionary adaptation. Menopause is adaptive, the argument goes, in the sense that women’s reproductive capacity is cut short barely two-thirds of the way through their lives so that the grandmother can help raise the grandchildren, thereby improving the survival of her lineage.

In spite of its appeal, however, “I’ve always thought that was a dumb theory,” says Holmes.

Much of the impetus for the grandmother hypothesis stems from the assumption that menopause is unique to humans.

It’s not, says Holmes. Guppies, for example, also experience menopause and then have a post-reproductive lifespan. Something like menopause occurs in many mammals, some birds, fishes, “animals where you wouldn’t expect care of your grandchildren to play any part in reproductive aging.”

A colleague of Holmes, David Reznik of University of California, Riverside, had long studied the evolution of aging in guppies.

They were having lunch one day at a professional meeting, “And I said, ‘Well you know, selection by predation should shape reproductive lifespan, but it shouldn’t shape the post-reproductive lifespan,’ ” says Holmes.

The post-reproductive lifespan is “evolutionarily irrelevant,” she proposed.

“Evolutionary theory predicts that if animals evolve under certain mortality pressure, it will shape the evolution of their reproductive lifespan,” says Holmes.

Reznik selected two populations of guppies to test that idea, one that had evolved under heavy predation pressure and another that had evolved under light predation pressure.

Once they analyzed their data, the researchers found that the two regimes did have different impacts on the guppies’ lifespans: “But it wasn’t quite the direction you’d expect,” says Holmes.

If an animal like a guppy lives in a stream with lots of other fish that want to eat it, says Holmes, one might assume that the population is selected to mature more quickly and have a shorter lifespan.

For some reason, the guppies that evolved under the heavy predation pressure not only started reproducing earlier, but actually lived longer.

However, as Holmes predicted, the mortality selection did not have an impact on their post-reproductive lifespan.

In other words, post-reproductive lifespan “seems to be a random add-on at the end of the life history.”

Although the appeal of the grandmother hypothesis is strong, the impulse to care for one’s grandchildren apparently is simply cultural rather than evolutionary in scale. “From an evolutionary standpoint,” says Holmes, “it doesn’t make any sense that you give up your own reproduction to promote the reproduction of your kin. The selection is too weak.

“It was good to get that paper published,” she says, “because a lot of people claim that menopause is unique to humans, and it’s not...

“The grandmother hypothesis is popular because feminists like it, it’s very woman friendly. When evolutionary biologists critiqued it, they were accused of being sexist. So it’s good to have my name on it.”

Categories: Biological sciences | Tags: Evolutionary biology, Menopause, Evolution

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