Welcome to Methods in experimental ecology PCB 6466
19 Slides4.73 MB
Welcome to Methods in experimental ecology PCB 6466
Instructors: Lina Sánchez Clavijo, Office: Biology Bldg. 409 [email protected] Office hours: Pedro F. Quintana-Ascencio, Office: Biology Bldg. 401 E [email protected] Office hours : by appointment With the participation of: Matthew Tye
First reading
Link to course web site http://pascencio.cos.ucf.edu/ Course Based on: Gotelli, N. J & A.M. Ellison. 2004. A primer of ecological statistics. Sinauer. Crawley, M.J. 2005. Statistics: an introduction using R. McCarthy, M. 2007. Bayesian methods in ecology. Cambridge.
Performance Evaluation: 13 exercises. We only consider the 10 best (5 points each) 5 x 10 50 Two exams: content cumulative (15 points each) 15 x 2 30 Final (20 points) Total 50 30 20 100 Grade scale: A 90-100; B 80-89; C 70-79; D 60-69; F below 60
Etiquette for communication Do not wait to the last minute. There will not be any response to questions within 24 hours before homework or exam due date. We like our weekends, please no e-mails on Saturday and Sundays. We will respond first come first served on Monday
Exercises E-mail a single Word document with your results. All analytical work needs to be done in R (unless otherwise noted). Scripts and output from R should be included in the Word document for full credit. They will be due a week from the day they are assigned. No assignments will be accepted after the start of the class on due date
Species correlates of Florifacies mirabila in playa linda Pedro Quintana-Ascencio Universidad de Cancun, Yucatan, Mexico
Florifacies mirabila Small mammal Feed on insects. It has glandules around the mouth producing a sweet secretion that attract plant pollinators. It is extremely sedentary Endemic to the Yucatan peninsula
Thorny plant (Opuntia sp.)
Objective To evaluate the association between Florifacies and Thorny plant (Opuntia sp.) Hypothesis Because both have flower like structures Florifacies and Thorny plant will be positively associated
Methods I established 59 1 x 2 m plots I counted every individual of Florifacies and Thorny plant (Opuntia sp.) within the plot Data was entered in Excel and analyzed with SPSS software
Nice Palms Quadrats Pedro Florifacies mirabila Thorny plant Sampling design
Are Florifacies and Thorny associated ? Florifacies Total Absent Present Thorny Absent 46 4 50 Present 4 5 9 50 9 59 Total Likelihood ratio 10.155, d.f. 1, Asymptotic significance (2 sided) 0.001 3 cells (75.0%) have expected count less than 5. The minimum expected count is .17
Do Florifacies density correlates with thorny plant density? How? 45 N 59 quadrats Florifacies density 40 35 30 25 20 15 10 y 0.36 x - 0.3654 R2 0.5551 5 0 0 20 40 60 80 Density of thorny plants 100 120
Conclusions Florifacies and Thorny plant (Opuntia sp.) are associated (P 0.001) Their densities are are positively correlated (P 0.001) My hypothesis was correct
What is wrong? Do you agree with this conclusions? Is the experimental design acceptable? Is the analysis correct?
How can we access this door? Experimental design and Data Analysis
What we need? ?