 Ecology is the relations of organisms with one another and with their physical surroundings. As such, ecology is very broad in scope and encompasses an incredible variety of research questions. Research in ecology encompasses everything from the effects of weather patterns on animal migrations, how nutrients cycle in a pond, to how humans interact and influence their local environments. Because of the breadth of ecology's scope, it is often broken into subcategories like terrestrial ecology, behavioral ecology and urban ecology. In this video, we will focus on urban ecology, which is the study of ecology where humans are abundant and have made significant changes to the local environment such as cities. Urban ecology presents unique challenges to the scientists who study it because of the abundant anthropogenic or human influence. These challenges include potentially restricted access to study sites, human interference in these study sites and the loss of study subjects due to human interference. Another interesting aspect of urban ecology is how fragmented or tiny a study can be. City parks are a great example of fragmented areas. Often, parks are the only available habitat for many species and so those species can be confined to areas that are widely scattered throughout the city. City parks also tend to be quite small, which greatly limits the size and types of animals and plants that can survive in them. In spite of the challenges, studying the ecology of urban environments allows scientists to ask unique and interesting questions about the world that cannot be addressed in more wild environments. Questions like, how does a bird's song change in a noisy city environment or even what is the best way to preserve an endangered species in an urban park are all part of urban ecology. These questions and others like them allow us to more fully explore and understand the urban environments in which over half the world's population resides. Urban ecology also helps us better understand the plants and animals that live alongside us in these environments. Can you think of some animals that are commonly found in urban environments? Pause the video and have a think. The list is too long, but some examples are rats, pigeons, dogs, cats, cockroaches and even monkeys. While humans are generally the dominant species in an urban environment, they are hardly the only ones. Learning to live with other species in an urban environment and understanding how our activities affect those species is another important aspect of urban ecology. Regardless of the specific study in question, urban ecology helps us not only build our understanding of an urban environment but also build better cities for humans and non-humans alike. So the next time you're out in an urban environment, take a minute to pause and really look at what's going on around you. You might be surprised at what you find.