Eating kangaroos instead of cattle and sheep has been given a scientific stamp of approval by
the government’s top climate change adviser.
The belch（嗳气） of millions of farm animals is a major contributor to Australia’s greenhouse
gas emissions（排放）, notes professor Ross Garnaut in a major report to the government on global warming.
Kangaroos, on the other hand, breathe out little amounts of methane（甲烷） gas.
If farmers were included in a system requiring industry to buy permits for the gas they
produce, the cost of meat would rise and could lead to a change in eating habits, says Garnaut.
“For most of Australia’s human history---around 60,000 years –the kangaroo was the main
source of meat,” he says.
“It could again become important. However, there are some barriers to this change, including livestock and farm management issues, consumer resistance and the gradual nature of change in food tastes.”
Garnaut cites a study looking at the potential for kangaroos to replace sheep and cattle for
meat production in Australia’s rangelands, where kangaroos are already harvested.
The study concludes that by 2020, beef cattle and sheep numbers could be reduced by seven
million and 36 million respectively, allowing for an increase in kangaroo numbers from 34 million now to 240 million by 2020.
This would be more than enough to replace the lost lamb and beef production, and kangaroo
meat would become more profitable than cattle and sheep as the price of emissions permits increased.
Garnaut’s report says livestock, mainly cattle and sheep, are responsible for some 67% of
agricultural greenhouse gas emissions.
Despite being the national animal and appearing on the Australian coat of arms, kangaroos are
slaughtered in the wild each year to control their numbers and much of the meat is used for pet food.
The idea of farming them for human consumption is controversial, but many Australians
already eat kangaroo meat.
55．Which of the following statements is true about kangaroos?
A．Kangaroos have appeared on a scientific stamp.
B．Kangaroos breathe out air containing little methane gas.
C．Kangaroos are the main source of meat for Australians.
D．Kangaroos are protected in a way because they are national animals.
56．All the following are factors that prevent kangaroos from being the main source of meat for Australian except ________.
A．Whether the price of the kangaroo meat is acceptable
B．Whether consumers like the new idea.
C．How the farms are run.         
D．Whether consumers become used to eating the meat
57．The underlined word “controversial” in the last paragraph is closest in meaning to ______.
A．acceptable         B．positive       C．negative       D．arguable
58．What’s the main idea of the passage?
A．Kangaroos may replace other animals in Australia in the near future.
B．People aren’t willing to eat kangaroo meat.
C．People are called on to eat kangaroo meat to reduce global warming.
D．Kangaroos pollute the environment less than other animals.