Insights from the 2018 American Society of Naturalists Awards
For over a century, the American Society of Naturalists (ASN) has championed a unique scientific mission: advancing knowledge of organic evolution and other broad biological principles to enhance the conceptual unification of the biological sciences 1 . Founded in 1883, this esteemed society represents one of North America's oldest professional organizations dedicated to biological research, fostering connections between ecology, evolution, behavior, and genetics.
Each year, the ASN recognizes exceptional scientists whose work embodies this integrative spirit, honoring researchers who reveal the fundamental patterns and processes that shape our natural world.
The 2018 ASN awards celebrated groundbreaking work that continues to reshape our understanding of life on Earth. From studying how evolution unfolds rapidly to influence which species coexist, to documenting the intricate relationships between organisms and their environments, these award-winning researchers have illuminated critical insights about biodiversity's origins and preservation.
One of North America's oldest biological research organizations
Bridging ecology, evolution, behavior, and genetics
For their groundbreaking paper "Eco-Evolutionary Buffering: Rapid Evolution Facilitates Regional Species Coexistence despite Local Priority Effects" published in 2018 2 .
Honors scientists who have made significant contributions to the knowledge of particular ecosystems or organism groups, bridging detailed observational natural history with theoretical biology 1 .
Recognizes emerging innovators whose initial contributions demonstrate exceptional promise for advancing conceptual unification in biological sciences 1 .
At the heart of the 2018 Presidential Award-winning research was a fascinating investigation into how rapid evolution influences species coexistence. Wittmann and Fukami's study addressed one of ecology's most enduring puzzles: how do competing species continue to coexist when classical theory predicts that one should inevitably exclude the other?
The researchers proposed and tested a novel mechanism called "eco-evolutionary buffering." This concept suggests that evolutionary changes occurring over contemporary timescales—not just geological ones—can maintain biodiversity by preventing competitive exclusion 2 .
When species first colonize a new area, the order of their arrival can create "priority effects," where early arrivers gain competitive advantages that exclude later arrivals. Wittmann and Fukami discovered that rapid evolution can mitigate these exclusionary effects, allowing more species to persist across regions than would otherwise be possible.
Their work challenged conventional boundaries between ecological and evolutionary timescales, demonstrating that evolution doesn't always proceed slowly over millennia but can occur rapidly enough to influence ecological outcomes here and now.
Rapid evolutionary changes maintain biodiversity by preventing competitive exclusion between species.
Wittmann and Fukami designed an elegant experiment using Saccharomyces cerevisiae (baker's yeast) and Tortulaspora delbrueckii (a related yeast species) to test whether rapid evolution can facilitate regional species coexistence despite local priority effects 2 .
Researchers established populations of two yeast species that compete for resources in synthetic nectar medium. Yeast provided an ideal model system because their short generation times allow observable evolutionary changes to occur rapidly.
They created local communities where each yeast species was given a head start—introduced at different times to establish priority advantages. This simulated the natural variation in colonization timing that occurs in real ecosystems.
The crucial manipulation involved comparing treatments where evolution could versus could not occur. Some populations allowed for evolutionary change over multiple generations, while others used a "no-evolution" control where populations were periodically replaced with frozen ancestral strains.
Researchers tracked population dynamics of both species over multiple transfer cycles (equivalent to generations), measuring their relative abundances and determining whether they could coexist or if competitive exclusion occurred.
The experiment examined coexistence at a regional scale comprising multiple local communities, testing whether evolution could promote biodiversity at larger spatial scales even when local exclusion happened.
This experimental design cleverly isolated the specific effect of contemporary evolution on species coexistence patterns, a challenging factor to measure in most natural systems but crucial for understanding biodiversity maintenance.
Yeast species were chosen for their rapid generation times, allowing researchers to observe evolutionary changes within a practical timeframe that would take much longer in most other organisms.
| Experimental Condition | Local Coexistence | Regional Coexistence | Competitive Exclusion |
|---|---|---|---|
| No priority effects | Stable | Maintained | Rare |
| Priority effects without evolution | Unstable | Reduced | Frequent |
| Priority effects with rapid evolution | Variable | Maintained | Prevented |
The findings demonstrated that when evolution was permitted to occur, the yeast species were able to coexist regionally despite strong priority effects that would normally lead to competitive exclusion 2 .
| Trait Measured | Ancestral Population | Evolved Population | Ecological Consequence |
|---|---|---|---|
| Growth rate | Fixed for each species | Divergent between species | Reduced competition intensity |
| Resource use efficiency | Overlapping | More specialized | Niche partitioning |
| Inhibition effect | Strong | Weakened | Reduced competitive exclusion |
The researchers observed that evolution led to trait changes including modifications in growth rates and resource use efficiency that reduced the competitive asymmetry between species. This "niche modification" through contemporary evolution effectively lessened the exclusionary power of priority effects, allowing more species to persist across the landscape of local communities 2 .
Microbial experimental systems require specific tools and reagents that enable researchers to study ecological and evolutionary processes under controlled laboratory conditions.
| Reagent/Resource | Function in Experiment | Biological Significance |
|---|---|---|
| Synthetic nectar medium | Controlled growth environment | Standardized resource base for competition studies |
| Model microbial organisms | Experimental subjects | Rapid generation times enable observation of evolution |
| Frozen ancestral stocks | Evolutionary controls | Allow comparison between evolved and ancestral populations |
| Selective inhibitors | Species-specific marking | Enable tracking of mixed populations |
| Flow cytometer | Population density measurement | Precise quantification of species abundances |
| DNA sequencing | Genetic change tracking | Identification of mutations underlying adaptation |
This research toolkit enables scientists to manipulate, measure, and monitor evolutionary ecology processes with precision that would be impossible in most natural systems. The controlled simplicity of microbial model systems provides powerful insights into universal biological principles governing ecosystems of all types.
The recognition of Wittmann and Fukami's work by the American Society of Naturalists highlights its significance in advancing conceptual unification across biological disciplines. Their research blurs traditional boundaries between ecology and evolutionary biology, demonstrating that these processes operate synergistically across similar timescales to shape biodiversity patterns.
The concept of eco-evolutionary buffering has profound implications for understanding how natural communities respond to environmental change. In habitats fragmented by human activities or climate change, rapid evolution may serve as a crucial mechanism maintaining biodiversity despite disrupted ecological interactions.
Conservation strategies might therefore benefit from considering evolutionary potential—not just current diversity—when planning protection measures. As we face escalating biodiversity crises, recognizing these dynamic evolutionary processes becomes increasingly important.
The 2018 ASN award-winning research exemplifies how sophisticated experiments with humble organisms like yeast can reveal universal biological principles, reminding us that nature's complexity often conceals elegant mechanisms that sustain life's magnificent diversity.
The American Society of Naturalists continues to champion integrative research through its awards program, annual meetings, and flagship journal The American Naturalist.