Bergmann’s and Allen’s rule suggest that for the same species individuals found further north, tend to have larger body sizes and smaller appendages compared to individuals further south, respectively, due to constraints for thermal regulation. This has shown especially true for birds and mammals.  In this paper, I test to see if global warming has led to a change in morphology for birds, i.e. body weight and wing size. We use year as a proxy for temperature as global warming has on average lead to an increase in the earth’s surface temperature over the last century with most of the change occurring since the 1980’s.  To test the hypothesis, I gathered data of male, young of the year birds during autumn migration for a select number of species with different wintering strategies, i.e. resident to long-distance migration. This data came from two Swedish bird observatories where standardized wing and weight measurements have been collected since 1986, coincident with the observed climate warming. The results of this study show that during this period, changes in body mass and wing length did not support the hypothesis that global warming has had a broad impact on the morphology of birds. Given that these results contradict that of other studies, analysis from species across a much wider latitudinal breadth of Europe, including, additional species and different age and sex classes should be investigated.

This study examines the impact of forest age on bird morphology and feeding guilds within the Kibale National Park, Uganda. Bird morphology is closely linked to their environment, effecting their ability to find food, avoid predators, and attract mates. Species characteristics in bird communities could change along the forest successional gradient, as different species or guilds exhibit preferences for specific stages of forest succession. Habitat preferences, such as the availability of nesting sites, foraging opportunities, and food availability, can be directly affected by changes in forest age. Life history traits like reproductive strategies and tolerance to disturbance and ecological interactions, such as competition, predation, and mutualism, can also be influenced by forest age. Changes in forest structure and resource availability can alter these dynamics, leading to shifts in species composition and community structure.  In this work data was derived from a study conducted in 2016, following the restoration of the Kibale National Park were the feeding guilds and morphological traits of birds were gathered from observed specimens in different aged forests to see if these traits change along the age gradient.  Understanding the relationship between forest age and species characteristics is crucial for effective conservation and management strategies. Conservation efforts often involve maintaining or restoring habitat conditions that support key species populations, which may include managing forest age structure to meet specific ecological requirements. By examining the data and working the statistics, significance could be found in all cases regarding bird traits and total number of individuals, with an increase in variables when compared to forest of primary age. Significance was only found in insectivore/nectivorous (IN) feeding guild with significance difference between forests of younger-primary age and older-primary age, and the sallying insectivorous (SAL) feeding guilds with no significant difference between the forest ages.