Butte Valley is home to around a dozen breeding raptor species, between the only national grassland in California, and surrounding agricultural farms such as strawberries, alfalfa, barley, and garlic. There is not an abundance of habitat selection due to agriculture farms, and the most common tree species used by nesting raptors in this area is western juniper (Juniperus occidentalis), followed by ponderosa pine (Pinus ponderosa) and some have nested on platforms on electrical poles and pivots. I collected microhabitat data from occupied nest trees to determine what type of tree characteristics Swainson’s (Buteo swainsoni) and Red-tailed Hawks (Buteo jamaicensis) prefer for their nest trees in Butte Valley, California. These microhabitat data were collected alongside longterm population monitoring efforts. Microhabitat data collected included tree height, nest height, number of trunks, diameter at breast height, density of canopy, the presence or absence of lichen and type, and doing the point-centered quarter method to collect these data at the nest tree and nearest neighbors to compare their availability in the environment. We expect Swainson’s and Red-tailed Hawks prefer older and larger tree characteristics. The implication of these results could inform which trees are selected for western juniper removal, which is an anticipated treatment in Butte Valley by the U.S. Forest Service.

Anthropogenic climate change forces organisms to adapt to rapidly changing environments and colonize new habitats, as their survival and fitness depend on their ability to respond to novel ecological challenges. How animals respond to these challenges and (sometimes) opportunities is not well understood. Here, we use the three-spined stickleback fish Gasterosteus aculeatus to ask how adaption to novel environments is reflected in the genetic population structure, neuromolecular processing, and neuroanatomy of three sensory modalities – olfaction, vision, and mechanosensation. Originally a marine species, sticklebacks have invaded freshwater lakes and streams across the Northern hemisphere, exhibiting an impressive capacity to adapt to widely different environments. Focusing on the waters of Iceland, we collected individuals from eight populations from marine, lowland spring-fed, highland spring-fed, and highland glacial environments, which vary in turbidity. We first assessed the transcriptomes of three sensory brain regions involved in olfaction (olfactory bulb), vision (optic tectum), and mechanosensation (torus semicircularis) and identified gene expression variation associated with ecotype. We then identified SNPs across the entire transcriptome and asked whether genes that contribute to the genetic population structure and are also differentially expressed might be casual to the differences. We also associated quantitative neuroanatomic traits including brain area and volume with turbidity across populations. Our results reveal how variation in selective pressures and evolutionary divergence is reflected in genetic, transcriptomic, and anatomic changes in the brain.

Leaf senescence is the successive process in which older leaves mature and then die, indicated by leaf yellowing. This is a critical developmental stage in all plants, including the model species Arabidopsis thaliana, and is imperative to the plant’s fitness, as nutrients are recycled back into the growing and storage tissues of the plant. The WRKY gene family encodes transcription factors that play critical roles in response to abiotic stressors. WRKY57 gene expression is induced by drought and overexpression of WRKY57 results in drought tolerance. Our lab is interested in WRKY57 as it may also be important for the regulation of leaf senescence in response to flowering, termed bolting in Arabidopsis thaliana. My project is to monitor WRKY57 gene expression after bolting and to isolate wrky57 T-DNA mutants and determine if they display early senescence. Two T-DNA insertions, SALK_006206 and SALK_076716, localize to the WRKY57 gene. To identify individuals that were homozygous for mutant alleles, we used PCR primers that spanned the insertion site. Two homozygous individuals were isolated for each T-DNA insertion. These PCR products were then sent for sequencing, after which we designed real-time qPCR primers to quantify WRKY57 transcripts. The WRKY57-1 primer pair amplified cDNA linearly and was used to quantify transcripts in response to bolting. We found that WRKY57 was up-regulated. Next, we will determine if T-DNA insertion lines block WRKY57 gene expression, and will quantify bolting-associated leaf senescence through loss of chlorophyll and activation of NIT2 gene expression.