Cancer evolution cannot be observed directly in patients, and new methodologies are needed for obtaining a quantitative understanding of this obscure process. We developed and analyzed a stochastic model of malignant transformation in the colon that precisely quantifies the process of colorectal carcinogenesis in patients through loss of tumor suppressors APC and TP53 and gain of the KRAS oncogene. Our study employs experimentally measured mutation rates in the colon and growth advantages provided by driver mutations.
Open to the public.
- Thu, Feb 18, 2021, 12:30 pm
- Thu, Apr 22, 2021, 12:30 pm
Urban ecosystems are intrinsically heterogenous, characterized by dynamic biotic and abiotic interactions that are not witnessed in non-urban environments. Urban flora and fauna experience a suite of novel disturbances and stressors that have led to remarkable phenotypic strategies and adaptations to cope with urban living. Despite recent groundbreaking discoveries and innovation in the fields of urban ecology and evolution, the drivers of urban heterogeneity that induce biological change are seldom articulated.
- Thu, Feb 11, 2021, 12:30 pm
- Thu, Apr 15, 2021, 12:30 pm
Germline stem cells (GSCs) in the gonads of animals are responsible for the sustained production of sperm and eggs, known as spermatogenesis and oogenesis, respectively. The Bag of marbles (bam) gene is essential for male and female fertility in the fruitfly Drosophila melanogaster and signals self-renewal and differentiation of GSCs. Surprisingly, we found that this gene has undergone strong positive selection for amino acid diversification in several closely related Drosophila species, but not in others.
- Thu, Apr 8, 2021, 12:30 pm
Dragonflies and damselflies, representing the insect order Odonata, are among the earliest flying insects with living (extant) representatives. However, unravelling details of their long evolutionary history, such as egg laying (oviposition) strategies, is impeded by unresolved phylogenetic relationships, an issue particularly prevalent in damselfly families and fossil lineages.
- Thu, Apr 1, 2021, 12:30 pm
How predictable is evolution? If we placed similar starting populations into replicated similar environments and then watched evolution happen, would each replicate population evolve in a predictable, deterministic way? Or, is evolution fundamentally unpredictable, dominated by chance events during and after colonization? Repeated evolution, often called ‘parallel evolution’, is taken as strong evidence for the role of natural selection in driving deterministic evolutionary change.
- Thu, Mar 25, 2021, 12:30 pm
- Thu, Mar 18, 2021, 12:30 pm
Among human activities, agriculture is a large emitter of greenhouse gases, the largest user of freshwater, and the largest polluter of water. Yet food is a necessity, and people want food to be inexpensive. In the Great Lakes region, North America’s breadbasket and water tower, conflicts around agriculture and water are ongoing. The Yahara Watershed around Madison, Wisconsin exemplifies these conflicts.
- Thu, Mar 11, 2021, 12:30 pm
The International Geological Association places the official starting date for the Anthropocene at 1950. Do the 60% of primates, 30% of amphibians and 21% of fish species threatened with extinction care? Those of us studying the human/other-animal interface needed no official sanction to denote contemporary rapid, radical and dramatic ecosystem churning. Human-animal interfaces represent critical loci for a majority of research in ecology, behavior and evolutionary biology.
- Thu, Mar 4, 2021, 12:30 pm
The mating system, or who mates with whom, and how often, is a critical trait that influences the distribution of genetic variation among populations as well as fitness and the ability of populations to respond to selection. Although we know that the plant mating system is strongly influenced by environmental factors, we do not understand if and how the mating system may be shaped by anthropogenic forces.