BIOLOGY 247: Climate Change and Phenology Project Maggie Weber, Haaris Jamal, Hallie Toren, and Nas Manai 1) Given our discussion of physiological ecology, energy budgets, and life histories, why might a shift in annual temperature over time due to climate change lead to changes in phenology (timing of life history events). Regular seasons play an important role in the organization of organisms' energy budgets . With this shift in temperature, the biophysical environment itself changes which disrupts the usual temperature dependent cues, leading organisms to alter their energy budgets which could then lead to reduced growth, out of sync mating seasons, and less energy storage if the resources become reduced. All of this can lead to a significant overall decrease in fitness in most individuals. 2) Create a graph of annual temperature over time. Consider the appropriate graph type and make sure that you label your axes. Based on your graph, how has annual temperature changed over time in British Columbia? The equation for the trendline shows a slope of 0.009, which means that the temperature rises about 0.009 ˚C each year on average. It is safe to say that the annual temperature in British Columbia has been gradually increasing over the last 115 years. 3) Natural history collections are rich repositories of biodiversity data. We can use information from specimen labels to compile data about phenology. Specifically, the date that a butterfly specimen was collected represents a day during which the butterfly was in flight. Create a graph to visualize if phenology (i.e., butterfly flight date) has changed over time. Consider the appropriate graph type and make sure that you label your axes. Based on your graph, how has the phenology of these butterflies shifted over time? Overall, there is very little change in phenology (flight date) of these butterflies from 1920 to 2020. There is only an extremely minor positive slope indicating a later flight date of the butterflies over time. 4) Estimate the slope of the relationship between butterfly flight data and year that you plotted above. In Excel, you can do this by adding the equation to the plot. In R, you can use the lm function. How does your estimate of phenological shift from Question 3 compare to the estimate from Kharouba and Velland that is provided in Table 1 of their article? Why is this? Slope: y=0.1399x-107.76 In Table 1 of their article, Kharouba and Velland found that the phenological shift of butterflies had a p-value of 0.50 meaning that the shift over time was not statistically significant. This supports my estimate of phenological shift from Question 3 because both demonstrate a non significant change in phenology (flight date) of the butterflies over time. (The mean coefficient was 0.0095, the total df was 121, and the t-test statistic was 0.68.) 5) Create a graph to visualize the relationship between butterfly flight date and mean spring temperature. Repeat with mean summer temperature instead of spring. Consider the appropriate graph type and make sure that you label your axes. Based on your graphs, how does the phenology of butterflies relate to temperatures in each season? When mean spring or summer temperature is higher, butterfly flight date tends to be slightly earlier in the year. This correlation may exist because higher mean temperatures lead to butterflies experiencing their trigger for first flight (a certain warm temperature) earlier in the year. The negative correlation between mean spring temperature and butterfly flight date is more distinct in Spring than in Summer. 6) Is the change in temperature the cause of the changes in phenology? Why or why not? While there is a slight negative correlation between mean spring and summer temperatures and butterfly flight date, we cannot draw conclusions about a causal relationship without running an experiment. 7) Kharouba and Velland found that plants are more sensitive to temperature than butterflies. Using the figure and values you derived in Question 5 as a reference, describe how a plot of the phenology of temperature-sensitive plants vs. temperature would compare to your butterfly plot. A measure of plant activity (i.e the number of days until the plants flowers bloomed) would be plotted on the y-axis, and the x-axis would represent (temperature). The temperature-sensitive bloom earlier in the year as mean temperatures increase. This would model the graphs seen in question 5, however the negative slope would be of a greater magnitude as the plants are more temperature sensitive in accordance to the question stem. Thus the negative correlation between mean temperature and flower blooming date would be seen in both the spring and summer as seen in the graphs of question 5. Below is a visualization of the more magnitudinous slope being exhibited by temperaturesensitive plants compared with the less temperature sensitive butterflies. (Not to scale) 8) How would you recognize if an ecological mismatch was possible between butterflies and their host plants? Draw a plot that would suggest an ecological mismatch. An ecological mismatch between butterflies and their host plants would occur due to flower blooming occurring before or after the time at which the butterfly population has populated the are where the flowers are. The butterflies would essentially miss obtaining the benefits from their host plant (i.e nectar or a place to lay eggs) and a key pollinator would be missed by the plant. Mismatch is likely because they are temperature-sensitive and will likely bloom ahead of the peak of butterfly migration. The top plot shows an ecological mismatch in terms of the peaks of each organism (bloomed flowers and butterflies) and the bottom plot suggests an ecological mismatch in terms of the date and temperature. 9) List the contributions of each of your group members to this assignment. Nas Manai (Questions 1-2) Hallie Toren (Questions 3-4) Maggie Weber (Questions 5-6) Haaris Jamal (Questions 7- 8) After meeting as a group on Zoom initially to discuss the project and our selected questions, we worked on the project separately and then came back together for another group meeting to discuss and refine our answers.
