What does it mean to say that we are "fishing down the food chain"?
What will be an ideal response?
Sizes of caught fish decline with higher rates of fishing. As we overfish the seas, we have largely eliminated stocks of large predators, many of whom are adult commercial fish species and are keystone species. Now we are fishing our way through more moderately sized consumers. Because food chains are not infinitely long, we will eventually be left with only primary consumers, which may not be very palatable. The removal of keystone species from any food has cascade effects that can produce serious and far-reaching disruptions. These include the possibility of allowing other species to replace the decimated fish species as new top consumers.
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Fewer than ?? percent of tropical disturbances evolve into tropical
cyclones. Based on what you’ve learned about tropical cyclones, why do you think this percentage is so low? What will be an ideal response?
What has been the consequence of China's "one -child" policy?
A) Average total fertility rate has dropped to 1.6, but the number of baby boys far exceeds the number of baby girls because of gender-selective abortion and abandonment of healthy baby girls at birth. B) The average total fertility rate has declined to 1.6. C) Chinese have emigrated to Japan by the millions to escape the policy. D) The total fertility rate has increased as people routinely break the law to have large families. E) The number of baby girls far exceeds the number of baby boys.
You have an air mass at 10°C that contains 1.8 grams of water vapor per kilogram of air (g/kg) (content). Air at 10°C has a maximum specific humidity of ______________ grams (capacity). Using the equation given at the beginning of Section 1, what is the present relative humidity of this air mass? ______________
Show your work:
You are hiking in the desert in Namaqualand in South Africa and you notice an area covered
with white sedimentary deposits. You taste the deposits and they taste salty. This is most likely an example of a. an evaporite. d. a pyroclastic rock. b. a metamorphic rock. e. a volcanic rock. c. a detrital sedimentary rock.