Extinction: Natural or Preventable?
What is extinction?
The permanent disappearance of a species.
What is natural selection?
The process by which heritable traits that improve survival or reproduction become more common over generations
What does biodiversity mean?
The variety of life, diversity within species, between species and across ecosystems.
Who argues that extinction is an unavoidable part of evolutionary history and shouldn't automatically be treated as a tragedy?
What three birds did Safina use as examples of successful conservation efforts?
Bald eagles, peregrine falcons, and ospreys
Did Pyron consider extinction a natural part of evolution or something humans should always prevent?
A natural part of evolution.
Which author argued that extinction helps create opportunities for new species to evolve?
Pyron
Did Pyron believe conservation should primarily protect all species or focus on ecosystems important to humans?
Focus on ecosystems and species important to human survival and well-being
Who argued that humans have an ethical responsibility to prevent unnecessary species extinctions?
Safina
What animal did Pyron compare humans to when discussing how species modify their environments?
Beavers
What distinction did Safina make between natural extinction and human-caused extinction?
Humans can recognize their choices and prevent the extinctions they cause.
What processes drive evolutionary diversification more directly than extinction itself?
Survival, competition, adaption, and specialization
What is the term used to describe the number of different species found within a particular area?
Species richness
Who compared human alteration of habitats to beavers constructing dams?
What pesticide contributed to the decline of several bird populations discussed by Safina?
DDT
Why did Pyron argue that the disappearance of a species doesn't necessarily mean a permanent loss of biodiversity?
New species can eventually evolve and diversify over time.
What evolutionary process allows surviving lineages to diversify into ecological niches left vacant after a mass extinction?
Adaptive radiation
What term describes the disappearance of a species from a particular geographic area, even though it continues to exist somewhere else?
Extirpation
Who argued that the recovery of species affected by pesticide use demonstrates the effectiveness of conservation?
Safina
What invasive plant did Pyron discuss as an example of a nonnative species that can provide environmental benefits?
Phragmites (common reed)
Why did Safina disagree with the idea that future evolution makes present-day extinctions less concerning?
Evolutionary recovery can take millions of years, and lost species cannot just be replaced on human lifespan
How did Pyron and Safina differ in their interpretations of extinction's role in evolution?
Pyron emphasized extinction as an opportunity for new evolutionary diversity, while Safine emphasized diversification through the survival and adaption of organisms.
What term describes the disappearance of an ancestral species because it gradually evolves into a new species, rather than drying out completely?
Pseudoextinction
Who argued that extinction itself is not the main source of evolutionary diversification, and that the continued existence of species is essential for further evolution?
Safina
What national park did Safina visit when he encountered bears, which inspired his discussion about the importance of protecting wildlife?
Katmai National Park in Alaska