Changes in the orbit of the earth caused the ice sheets to spread across Canada.
Answer:
over 4.5billion years ago is the answer
Explanation:
Answer:
prohibits the introduction of invasive species
controls the kind of waste and pollutants allowed
assesses human influence on the environment
designates protected zones on the continent
Explanation:
These four key terms are some of what the Madrid Protocol includes.
Prohibiting the introduction of invasive species keeps the ecosystem from being dominated and/or destroyed by a single species that the ecosystem is not built to handle.
Controlling the kind of waste and pollutants allowed on the continent ensures that the environment remains stable without the influence of outside chemicals, such as oil or carbon emissions that could harm the ecosystems.
Assessing human influence on the environment keeps track who does what and how they do it, essentially preventing extreme human action from being taken so as to preserve Antarctica's natural order.
Designating protected zones on the continent that can only be accessed with special permits ensures that only people who require access for research or whatnot, or more simply, qualified personnel, are able to enter these zones, so as to keep contact down to a minimum and further preserve Antarctica's natural environment.
