Nature, Science

Why Are Swiss Stickelback Fish Evolving So Fast?

A population of stickleback fish is rapidly splitting into two distinct species in Switzerland’s Lake Constance.
A population of stickleback fish is rapidly splitting into two distinct species in Switzerland’s Lake Constance. Photo: EAWAG | David Alexander Marques.

There is a concept in evolutionary biology called sympatry, in which two interbreeding populations develop unique genetics and evolve into two species.

Sympatry is a rare biological event. Conventional biology has assumed that speciation only occurs when a mountain range or some other type of geographical or geological feature separates two populations. Increasingly though, sympatry has been gaining ground as more and more researchers seem to be finding it among their subjects.

Most recently, researchers in Switzerland have discovered that two populations of three-spined sticklebacks in Lake Constance and its watershed streams are evolving along these lines.

Basically, one group favors the streams, and another favors the lakes. They show marked differences in size and armor, which could be chalked up to lifestyle differences, but there are specific genetic differences between the two groups.

The most interesting part though, is that they not only both breed in the same streams, but also continue to interbreed. This clear example of sympatry could tell us quite a lot about evolution.

The general assumption is that evolution requires significant periods of time to occur. However, the three-spined stickleback has only lived in those waters for about 150 years, which is the blink of an eye compared to evolutionary timelines. This isn’t the first example of evolution on this kind of timescale though.

Apple maggots evolved in North America within two centuries of apples being first introduced to the continent. Cancers become resistant to drugs. Insects develop resistance to pesticides. Bacteria develop resistance to antibiotics.

A major factor contributing to this process may be the average lifespan of such organisms, but it doesn’t change the fact that we’re finding, more and more, that evolution is capable of a wide variety of timescales.

Advertisements
Business, Conservation, Sustainability

Turning Sewage Water Into Something Drinkable

At Orange County’s Caspers Wilderness Park showers are currently unavailable for campers due to current drought conditions throughout the state of California.
At Orange County’s Caspers Wilderness Park showers are currently unavailable for campers due to current drought conditions throughout the state of California. Photo: Mechanoid Dolly | FlickrCC.

Dow Chemical Co. and Dupont Co., two American chemical industry giants that are 118 and 213 years old, respectively, recently announced a $130 billion merger deal that would take two years to complete. Led by activist investor Dan Loeb, hedge fund Third Point LLC suggested Dow Chemical split its specialty chemical and petrochemical businesses. As part of the deal, the merged company will split into three separate entities—focused on agriculture, specialty chemicals, and materials.

In the midst of this landmark deal, Dow is continuing to solidify its place as a leader in the industry—this time on behalf of California. As California continues to deal with one of the most severe droughts on record for the fourth year in a row, Orange County—with the help of Dow Chemical—is doubling down on its unusual strategy for drinking water.

Bloomberg recently toured the facility with Snehal Desai, Dow Chemical’s global business director of the water division. It’s the largest facility in the world that practices “toilet-to-tap” technology—a complex filtration system that transforms raw sewage into an end product that’s fresher than some bottled waters. The plant, located next to the county’s water treatment facility, pumps out 100 million gallons of drinking water daily, enough to supply almost 1 million Orange County residents. The county plans to increase the output of its groundwater replenishment system by approximately 50 percent.

“Recycled wastewater will probably be the single largest source of water for California over the next quarter century,” says executive director of the Association of California Water Agencies Tim Quinn. This goes for many other water-strapped regions of the world, including Australia, China, India, Israel, Spain, the Middle East, and sub-Saharan Africa, where they have developed recycled wastewater systems for irrigation. Many areas are beginning to convert their systems to create fresh drinking water. San Diego also recently announced plans to generate 33 percent of its water from recycled sewage by 2035.

Dow Chemical has been a dominant player in advanced materials engineering for more than 100 years, generating $57 billion revenue a year in 180 countries in the world. “If not Dow, then who?” asks Desai. “The future water supply is a big-ass problem. We’ve got growing urban populations, growing industries, and dwindling resources. Who can tackle something of this magnitude? You need patience and horsepower to come up with solutions and to scale them. You can’t do that without big-boy company money.”

Ultimately, Desai believes that the same technology could accommodate individual households. Every city in the world will have to start rethinking the foundation of its water supply. “Not every city has an ocean, not everyone has good lakes and rivers,” Desai says. “But everybody’s got sewage.”