The Earth has sustained life for billions of years. Would you like to know how it all works? This course published by Course Gate lays out the basic concepts of ecology. We trace the relationships between organisms and their physical environment. Our first module explores the ideas of the natural order of living things and evolution. We discuss the role of bacteria fungi and other microorganisms that have only been studied since the invention of the microscope.  The course defines the term ‘ecosystem’ which are crucial for ecological activities like the maintenance of life support systems and regulation of energy flow. We then examine natural resources the ‘pecking order’ and the role of competition within evolutionary niches. We then study how organisms adapt to environmental changes and identify the adverse effects caused by human activities. We discuss the difficulties caused by pollution including acid rain global warming the depletion of natural resources and other artificial challenges. We address the global concern of climate change. Climate is a major factor in the physical environment and ultimately determines water availability and thermal conditions. This section focuses on climate space adaptation and the effects of climate change. Finally we explore environmental conservation which is crucial in terms of preserving drinking water and the ozone layer and sustaining human and animal food chains via the prudent use of non-renewable resources. Sign up to learn how the natural world is arranged into ecosystems and what role you can play in preserving it.