The Blueprint of Life Chapter 1: Evidence of evolution suggests that the mechanisms of inheritance, accompanied by selection, allow change over many generations. Evolution is the gradual process of change in an organism over time. 1. Outline the impact on the evolution of plants and animals of: changes in physical conditions in the environment, changes in chemical conditions in the environment, competition for resources The impacts of evolution depend upon:  Variation (Individuals of a species vary within a generation)  Heritability (At least some of this variation will be passed on to offspring)  Excess production (More individuals are born than survive to reproduce.)  A population of organisms consists of many individuals characterised by a variety of inherited traits (variation). This influences the ability of the species as a whole to produce individuals capable of surviving changes in environmental conditions (natural selection).  An adaptation is any inherited characteristic (structural, physiological or behavioural) that increases an organism’s contribution to the future generations, or increasing its chances of survival. It is the process of change by which an organism or species becomes better suited to its environment.  It is the variation in genetic information passed on through generations together with adaptations to changing environmental conditions that drive evolution. Any new environment is said to exert selective pressure on organisms, and can cause adaptive change and evolution.  Evolution can occur when populations have sufficient variations so that better-adapted individuals survive in the new environment, then reproduce to pass on selective advantage, natural selection. Changes in Physical conditions: ¤ Includes any non-living natural conditions (abiotic) such as wind, temperature and availability of water Australian Eucalyptus Tree Australia was once covered by lush rainforests however as the climate changed due to the movement north, so did its vegetation. The soils became drier and rainfall dropped greatly. This, in turn, led to the evolution of the Eucalypt. Peppered Moths in England The traditional population of peppered moths in England were white with black flecks on their bodies. This allowed them to avoid predators by camouflaging into the lichen on the trees. However, in 1849, a coal black mutant moth was found near Manchester, England. Within a century this black form had increased to 90% of the population in this region. The industrial revolution had occurred during this time, increasing the amount of sulphur and nitrogenous dioxides in the atmosphere. Where air pollution is severe, the lichens turn black so the coal black mutant was able to camouflage and survive from predators. In areas far from industrial activity the lichens on the trees are white so the peppered moth population is white. Changes in chemical conditions: ¤ The concentration of chemicals in the environment that an organism uses or is adapted to may change. For example, the