RESEARCH INTERESTS
ABOUT ME:
At heart, I am a scientist and naturalist. I believe that only by incorporating a solid understanding of natural history into scientific pursuits can we fully understand the patterns and processes observed in nature. My interests focus on two broad topics of fish biology: breeding behavior and adaptation to different habitats. Adaptation and breeding are tightly linked to fitness and, thus, my research elucidates these vital underpinnings that are essential for a thorough understanding of the ecology and evolution of organisms and may also offer insights into conserving biodiversity.
CURRENT/FUTURE RESEARCH:
Despite hundreds of years of research and scientific inquiry, we still have a lot left to explore in the fields of fish morphology, behavior, ecology, and evolution!
1. APPLIED RESEARCH: Responses to urbanization/human activities
Very little is understood about how most species respond to urbanization and human-induced changes to the environment. These changes affect a suite of selective pressures, including water velocity and predator/prey abundances, but surprisingly little is known about how species respond- morphologically and behaviorally- to such modified habitats. By comparing heavily urbanized areas to more natural areas, I hope to explore the impacts of human activities on fish populations.
2. FOUNDATIONAL RESEARCH: Basic biology/natural history
Just like with the white lab rat, there are some "model" fish species- i.e. species that have been extensively studied (i.e. guppy and stickleback). However, for the majority of species, their basic biology and natural history is poorly understood. The literature is filled with examples of substantial variation in some basic biological responses to selective pressures, yet we do not know if this is due to interspecific or intraspecific variation. By conducting research with lesser known species, I hope to provide insights whether fish responses to various selective pressures are generalizable or very species-specific.
Opportunities for research in my lab exist in both the field and the lab. I gladly welcome (and strongly encourage) undergraduate students to contact me to develop their own ideas into an independent study project or to gain research experience by assisting me as a research assistant!
PAST RESEARCH:
1. Breeding Behavior My Master’s thesis focused on a life history trait, namely the age of first reproduction of smallmouth bass (Micropterus dolomieu). I explored why there was substantial variation within a cohort with regard to when male spawned for the first time. Through an analysis of three cohorts and calculating the lengths of individuals at younger ages, I demonstrated that the fish that spawned at the earliest age were those who had grown the fastest before the first winter. I also showed that the length of the spawning season that the males were born in played a large role in determining when they reproduce. A longer spawning season caused more disparity in the age of first reproduction than a shorter season. This research provides an ecological factor (spawning season) for the explanation of a life history trait (age at first reproduction), thus linking together two inter-related biological disciplines.
While at the University of Illinois, I performed an experiment wherein I examined the egg-laying behavior of the bluefin killifish (Lucania goodei) (see Welsh and Fuller 2011 below). In species with external development, egg placement is expected to impact the fitness of individuals via offspring survival. I found that females preferred to lay eggs in areas where eggs were already present, especially when clutch sizes were small. Females may be doing this behavior to increase the probability of offspring survival. What was especially novel is that this is one of the first studies to show that the preference for laying eggs where eggs were already present is not unique to species that build nests and provide parental care.
2. Adaptation My dissertation has addressed several questions related to morphological differentiation between lakes and streams and local adaptation to these different habitat types. I completed two comparative analyses utilizing morphometric techniques to explore body size and shape between lakes and streams- one across entire family and another within one species (the blackstripe topminnow (Fundulus notatus)). My analyses simultaneously examined multiple causative factors (age, sex, and habitat), which is uncommon in many experimental designs. Both within the family and the species, I found strong sexual dimorphism in body shape, but not size, and, contrary to expectations, strong effects of habitat on size, but not shape (see Welsh and Fuller or Welsh et al. 2013 below).
At heart, I am a scientist and naturalist. I believe that only by incorporating a solid understanding of natural history into scientific pursuits can we fully understand the patterns and processes observed in nature. My interests focus on two broad topics of fish biology: breeding behavior and adaptation to different habitats. Adaptation and breeding are tightly linked to fitness and, thus, my research elucidates these vital underpinnings that are essential for a thorough understanding of the ecology and evolution of organisms and may also offer insights into conserving biodiversity.
CURRENT/FUTURE RESEARCH:
Despite hundreds of years of research and scientific inquiry, we still have a lot left to explore in the fields of fish morphology, behavior, ecology, and evolution!
1. APPLIED RESEARCH: Responses to urbanization/human activities
Very little is understood about how most species respond to urbanization and human-induced changes to the environment. These changes affect a suite of selective pressures, including water velocity and predator/prey abundances, but surprisingly little is known about how species respond- morphologically and behaviorally- to such modified habitats. By comparing heavily urbanized areas to more natural areas, I hope to explore the impacts of human activities on fish populations.
2. FOUNDATIONAL RESEARCH: Basic biology/natural history
Just like with the white lab rat, there are some "model" fish species- i.e. species that have been extensively studied (i.e. guppy and stickleback). However, for the majority of species, their basic biology and natural history is poorly understood. The literature is filled with examples of substantial variation in some basic biological responses to selective pressures, yet we do not know if this is due to interspecific or intraspecific variation. By conducting research with lesser known species, I hope to provide insights whether fish responses to various selective pressures are generalizable or very species-specific.
Opportunities for research in my lab exist in both the field and the lab. I gladly welcome (and strongly encourage) undergraduate students to contact me to develop their own ideas into an independent study project or to gain research experience by assisting me as a research assistant!
PAST RESEARCH:
1. Breeding Behavior My Master’s thesis focused on a life history trait, namely the age of first reproduction of smallmouth bass (Micropterus dolomieu). I explored why there was substantial variation within a cohort with regard to when male spawned for the first time. Through an analysis of three cohorts and calculating the lengths of individuals at younger ages, I demonstrated that the fish that spawned at the earliest age were those who had grown the fastest before the first winter. I also showed that the length of the spawning season that the males were born in played a large role in determining when they reproduce. A longer spawning season caused more disparity in the age of first reproduction than a shorter season. This research provides an ecological factor (spawning season) for the explanation of a life history trait (age at first reproduction), thus linking together two inter-related biological disciplines.
While at the University of Illinois, I performed an experiment wherein I examined the egg-laying behavior of the bluefin killifish (Lucania goodei) (see Welsh and Fuller 2011 below). In species with external development, egg placement is expected to impact the fitness of individuals via offspring survival. I found that females preferred to lay eggs in areas where eggs were already present, especially when clutch sizes were small. Females may be doing this behavior to increase the probability of offspring survival. What was especially novel is that this is one of the first studies to show that the preference for laying eggs where eggs were already present is not unique to species that build nests and provide parental care.
2. Adaptation My dissertation has addressed several questions related to morphological differentiation between lakes and streams and local adaptation to these different habitat types. I completed two comparative analyses utilizing morphometric techniques to explore body size and shape between lakes and streams- one across entire family and another within one species (the blackstripe topminnow (Fundulus notatus)). My analyses simultaneously examined multiple causative factors (age, sex, and habitat), which is uncommon in many experimental designs. Both within the family and the species, I found strong sexual dimorphism in body shape, but not size, and, contrary to expectations, strong effects of habitat on size, but not shape (see Welsh and Fuller or Welsh et al. 2013 below).