Advanced topics in the ecology of populations: 1. Intraspecific like : properties, growth, competition and regulation. 2. Interspecific like: competition, predation, co-evolutionary interactions and human impacts on populations and predator-prey balance. Besides, topics related to communities like: structure, dynamics and succession of communities will be discussed. Characteristics of different ecosystems that are governed by environmental variability including grasslands, shrub lands, deserts and tundra in addition to freshwater and marine water ecosystems. Global environmental changes like greenhouse gases and global climate, sea level rise, plant production, and human health.