Chapter 9 review Lucas Collins

Section 1 Species are becoming extinct 1,000 times faster than when modern humans first arrived. But by the end of the twenty-first century, its expected to be around 10,000 times faster There are 2 types of extinction: Biological, which occurs when a species can not be found anywhere on the planet. Mass extinction, is the extinction of many species within a short period of time

Section 1 (cont.) There are two classifications for species that are on the way to becoming biologically extinct. Endangered, which has few individual survivors and could soon become extinct. Threatened, which still has enough to survive a short-term period, but eventually could become extinct

Section 1 (cont.) Some species have behavioral characteristics that make them more likely to become extinct. For example, the passenger pigeon traveled in large numbers, making them easier to be killed. Some species are more threatened to extinction because of human activities and actions Human activities were the result of the Passenger Pigeons’ extinction in 1900

Section 2 There are four major reasons why we should work to prevent the extinction of other species: Species are a vital part of the life support system Most species contribute to our economic services It will take 5-10 million years for natural speciation to rebuild biodiversity Many people believe that all species have the right to exist, even if they are not significant

Section 2 (cont.) We cannot protect all species from extinction so we must distinguish which are more worth saving. Most species that become extinct, we know little about and therefore are not fully able to protect them.

Section 3 HIPPCO: Summarization of the most important direct causes of extinction due to human actions H: Habitat destruction, degradation, and fragmentation I: Invasive species P: Population growth and increasing use of resources P: Pollution C: Climate change O: Overexploitation

Section 3 (cont.) The greatest threat to wild species is habitat loss. Invasive species, which are deliberately introduced into some ecosystems, can be very harmful and can majorly disrupt them

Section 3 (cont.) There are ways to reduce threats from invasive species: Fund a massive research program Increase ground surveys and satellite observation Identify harmful invader species and establish treaties banning transfers Require cargo ships to discharge their ballast water and replace it Educate the public about the effects of releasing exotic plants and pets into the environment

Section 4 The Endangered Species Act of 1973 was designed to identify and protect endangered species in the US and other countries It was the most far-reaching environmental act ever written In 1903, President T. Roosevelt established the first US federal wildlife refuge at Pelican Island, to protect birds from extinction

Section 4 (cont.) The precautionary principle: to take precautionary action to avoid causing more extinctions and more loss of biodiversity Scientist use it to argue for preservation and protecting of entire ecosystems Also used as a strategy for preventing exposure to harmful chemicals in the air, water, and food

Three Big Ideas 1. We as humans increase the extinction of species by degrading their habitats, introducing invasive species, population growth, pollution, climate change, and overexploitation of species. 2. We should avoid causing the extinction of species because of their ecological and economic services they provide 3. We can try to prevent the extinction of any species by using laws, protecting wildlife refuges, and increasing use of the precautionary principle