The Forgotten Naturalist

By Joykrit Mitra
BU News Service

Alfred Russel Wallace
Alfred Russel Wallace

At the time of his death in 1913, Alfred Russel Wallace was the most famous scientist in the world. He was acknowledged as the co-discoverer of evolution by natural selection, along with Darwin. He’d travelled the world, discovered thousands of new species, collected countless natural specimens and hobnobbed with natives closer than any Victorian gentleman would deem proper. But in today’s world, a scientist’s life rarely resembles an adventure story, and few remember him.

Some ideas we associate with Darwin were actually Wallace’s. Darwin’s trumpeters shoulder some blame for Wallace becoming a mere footnote, but so do common misconceptions about the 19th century.

Wallace was one of the most progressive men of his time, yet he attended séances and advocated phrenology, a pseudoscience that co-related intelligence with skull shape. Wallace seems a man of contradictions to modern eyes. Yet, a picture of Wallace that is surprisingly reconcilable with current ideas emerges when we examine the history of the idea of natural selection.

These days, the term natural history is less widely known than it was in its heyday in the 19th century. DNA had not been discovered, and biologists still looked for answers beyond the microscope.

In Victorian England there wasn’t much variety among organisms and fruits. Poets still thought that nature had arranged everything for the convenience of man. But Darwin and Wallace left their comfort zones and entered the wild. Here, man was intruder and nature was hostile. Both men encountered new species and other races. While they reached the same conclusion in one regard, they interpreted some observations differently.

Darwin resolved the conundrum of why males in certain bird species were highly ornamented— it increased their visibility to predators— by arguing that the males were selected to be bright and showy to affect female choice. But Wallace countered that brightness was the default state and females were the ones selected to be drab, for sake of camouflage, since they were sitting on the nests.

‘Survival of the fittest’ wasn’t Darwin’s idea either. Darwin thought male butterflies chose the most beautiful females via an innate aesthetic sense. Wallace argued that choice had nothing to do with aesthetics but that females were simply choosing stronger and healthier males.

“In his copy of Darwin’s writing, Wallace goes through and crosses out ‘natural selection’ and writes the term he prefers to use – Herbert Spencer’s term ‘survival of the fittest’,” says Wallace historian Andrew Berry.  “Wallace thought Darwin’s term implied an artificial selector who was influencing natural selection.”

Wallace was one of the rare non-racists of his time. Darwin experienced the Beagle voyage from a gentleman’s cabin, but Wallace’s working class upbringing had etched in him fewer inhibitions. His day-to-day interactions with “savages” convinced him they were not inferior, and could be schooled in the arts of civilization. But it also led him to propose something radical about the human brain, which resulted in a major break with Darwin.

Wallace proposed that once natural selection had honed the human body it moved on to the brain. But natural selection only endows traits that are immediately useful for survival. The “savages” he encountered were quick learners, despite the fact that nothing in their barbaric state could give rise to the mental faculties necessary.  Wallace concluded that the human brain was over-engineered, with innate faculties that were useless to man in a state of barbarism, but could be called into use later.

“What Wallace saw was that your local ‘savage’ had the same sized brain and equal mental capacities to that of a naturalist in Britain,” says George Beccaloni, curator of the Wallace Collection at Natural History Museum, London. “So how could it be that the human brain evolved to such complexity, more than is actually needed? How did this organ arise?”

Wallace’s answer did not please the Victorian scientific establishment. He declared a supernatural force had intervened, and was branded a heretic.

Wallace was a true renaissance man. He went on to earn praise from John Stuart Mill for a treatise on political economics, and founded the field of astrobiology.  His work ‘Man’s Place in the Universe’ was the first to speculate on conditions necessary for life on other planets. Today, he is recognized as the father of biogeography – the study of how different species are distributed in relation to land – and as one of the earliest conservationists.

“Wallace is seen more as a dilettante,” says Berry. “Darwin consolidated on his theory, kept publishing things in support of previous ideas. But for Wallace, it was just this one thing he did, and moved on.”

Wallace remained a materialist until very late in life. He continued to believe that everything in nature—apart from the human mind— could be explained by natural laws. Yet he never questioned the existence of a spirit world. Perhaps the reason Wallace is forgotten is that it makes us uncomfortable that a man of genius could comfortably straddle, what seems to us, such incongruent subjects.

Genetic Modification: Polarizing the population [infographic]

By Matthew Hardcastle and Poncie Rutsch
BU News Service

With all the angry voices chiming in on genetically modified foods, it can be really hard to figure out where the basic science stands. Lately, the conversation has been getting particularly ugly. People who support genetically modifying their foods (shortened to GMOs for genetically modified organisms) have started to proclaim that without genetic modification, people in the world will always be starving — that is, there is no other way to feed a growing population. Meanwhile, people who reject GMOs start to sound very similar to people suffering from climate denial — limited arguments based on poorly researched science.

We decided to put together a sort of GMO cheat sheet: what you need to know, some basic facts, and a few questions before you lose friends over this polarizing argument. We tried debating, but it felt mean and didn’t represent the amazing level of complexity that surrounds this issue. For this readon, there are occasions when the two paths overlap. In no way is this the end of the argument, but instead of reading another op-ed, why not get to the basics?

Reporting IN FAVOR OF GENETIC MODIFICATION is Matthew Hardcastle. His points follow the blue path.

Reporting LESS FAVORABLY ON GENETIC MODIFICATION is Poncie Rutsch. Her points follow the green path.




clickable map of world hunger.

A few more basics on what world hunger is and how it intersects with malnutrition.

Reporter Sharon Schmickle travels to Tanzania to explore GMO resistance through a Pulitzer grant.

One Equals Many: A New Take on Evolution

Looks someone needs some new microbes...
Looks someone needs some new microbes...
On the left is an example of a healthy coral, on the right an example of bleaching. Photo courtesy NOAA.

By: Sara Knight
BU News Service

When English poet John Donne claimed that “no man is an island,” he probably did not anticipate how closely his philosophical musings would align with biological theory four centuries later. As genetic research progresses, scientists are realizing that evolution may be more about cooperation among organisms than competition – truly, no organism is an island unto itself.

Biologists increasingly can pinpoint instances of interdependence among species in all kingdoms of life – leading some to believe it is time for traditional Darwinian theory to evolve. Mounting evidence of cooperation among diverse creatures and their respective microbial communities provides tantalizing hints of a more comprehensive view of life – one that challenges the definition of an organism. For decades many microbiologists have believed that no organism evolves alone, but rather as a joint effort with the millions of microscopic creatures teeming with them – fungal, bacterial, and protist. Now, evolutionary biologists are catching on: some think that natural selection acts on “super organisms,” the creature plus its microbes, rather than an organism itself.

Charles Darwin proposed the theory of natural selection in 1859, and it remains a hallmark of evolutionary biology today. Natural selection’s basic tenet is that traits that prove beneficial to an organism will become more common over successive generations. While this basic premise seems almost obvious in its simplicity, many evolutionary puzzles are left unaddressed. For example, the level of organization on which natural selection acts remained an enigma. Do evolutionary pressures act on cells themselves, or whole organisms… or even groups of organisms?

Biologists Eugene Rosenberg and Ilana Zilber-Rosenberg think they have the answer. In 2007 they proposed that organisms adapt to their environments with and because of their microbial communities. They noted that a change in the makeup of species in Mediterranean corals’ microbe population, prompted by changing sea temperatures, enabled the coral to fight off a devastating bleaching virus. The coral, which lacks an adaptive immune system, overcame a viral threat in one generation. The microbial community of the coral successfully fought off the lethal threat, ensuring its survival into another generation. Their observation led the team to develop the hypothesis that natural selection acts not just on one set of genes, but on all of the genes within (and on) an individual, including those of the micro-occupants.

Painting detail from Georges Seurat’s “La Parade de Cirque.”
Are we more than the sum of our parts?

All lifeforms possess robust microbial communities that are linked to physiologic function – humans, for example, rely on hundreds of species within our gut to digest our food and absorb nutrients. Hyenas have unique microbe collections in their anal glands, the distinctive scent of which acts as a badge of pack membership. The mixture of intestinal microbes in the common fruit fly influences with whom they choose to mate. Rosenberg believes these facts justify extending his team’s hypothesis to encompass all life, rather than just this specific Mediterranean coral.

Biologists have long accepted the importance of microbes to the lives of larger creatures – for example, the mitochondria in your own cells originated from a once free-living bacterium that was engulfed by a larger cell – yet many hesitate to agree with Rosenberg’s broad generalization of cooperative evolution in larger creatures.

Roberto Iglesias Prieto of the National Autonomous University of Mexico does not believe Rosenberg and his team proved that the Mediterranean coral was suffering from the viral perpetrator they identified. He, among other marine biologists, calls for a more rigorous examination of Rosenberg’s claim. Iglesias Prieto also cautions that an organism’s fitness might not rely on its entire set of microorganisms, but probably only its beneficial microbes.

Other biologists like John R. Finnerty, director of Boston University’s marine program echo this caveat. Finnerty does not question Rosenberg’s basic claim, but suggests the primary coral research does not support the larger hypothesis that natural selection acts on super-organisms. In some cases, a creature may need a very specific species of microbe to fill a role, while in others the co-occupancy is more of an incidental arrangement between the microbe and host, Finnerty says. The relationship between host and microbe can be very flexible – a fact that Rosenberg’s hypothesis does not address.

Despite these concerns, biologists are becoming more interested in the role our resident microbes fill. In 1998 microbiologist Lynn Margulis wrote that “the full impact of the symbiotic view of evolution has yet to be felt.” Her foresight anticipated Rosenberg’s ambitious, broadened concept of how to define an organism and a concept of evolution that stresses cooperation, rather than competition, as the main catalyst for change. Researchers are currently working toward teasing out the exact roles microbes play in the production of life, but there is a general-consensus that we literally are more than the sum of our parts.

Bobbing for Paganism

Ah the raw thrill of completely soaking one's trunk in pursuit of a crispy apple bobbing in pathogenic brine. Photo courtesy of flickr Creative Commons user Rob Swystun.
Ah the raw thrill of completely soaking one’s trunk in pursuit of a crispy apple bobbing in pathogenic brine. Photo courtesy of flickr Creative Commons user Rob Swystun.

By Poncie Rutsch
BU News Service

I’ve always wanted to bob for apples on Halloween but unfortunately, I grew up in the era of germaphobes. The first time I saw an actual bucket filled with water and apples primed for the bobbing, I was 12. Now people bob for apples on strings. Or in their own private buckets.

But why is it that people decided to stick their heads in a bucket of water in the first place?

Bobbing for apples supposedly dates back to pagan festival of Samhain, the beginning of fall. More recently, bobbing was used for fortune telling on the British Isles in the 19th century. Once a person caught the apple, they would peel it and toss the long peel over their shoulder, where it would supposedly form the letter of their true love’s first name on the floor.

What’s especially interesting is that the apples they would have bobbed for would not have tasted all that sweet. Sweet apples originated in Kazakhstan, but even there they were more likely to be pressed into hard cider than eaten.

The sweet apples we have today are the result of thousands of years of careful domestication. If you grow apples from seed, the results will be small and bitter; palatable, but not the apple of your dreams. The best apples come from grafting different species together.

After years of manipulation, many favorite apple varieties are lacking in genetic diversity. Breeders graft native crabapple species to choice trees to try and raise their diversity — to prevent the spread of disease or pests. They’ve done this so many times that apples in North America are now more closely related to crabapples than to their ancestors in Kazakhstan.

I particularly like that if you slice an apple in half at its equator, the seeds form a pentagram, classically associated with paganism.

So fortune telling, alcohol, paganism…sensing a theme yet?


When sliced across the equator, the seeds at the center of an apple forms a pentagram. Photo courtesy of flickr Creative Commons User Denise Cross.
When sliced across the equator, the seeds at the center of an apple forms a pentagram. Photo courtesy of flickr Creative Commons User Denise Cross.