题目材料
Until recently, zoologists believed that all species of phocids (true seals), a pinniped family, use a different maternal strategy than do otariids (fur seals and sea lions), another pinniped family. Mother otariids use a foraging strategy. They acquire moderate energy stores in the form of blubber before arriving at breeding sites and then fast for 5 to 11 days after birth. Throughout the rest of the lactation (milk production) period, which lasts from 4 months to 3 years depending on the species, mother otariids alternately forage at sea, where they replenish their fat stores, and nurse their young at breeding sites. Zoologists had assumed that females of all phocid species, by contrast, use a fasting strategy in which mother phocids, having accumulated large energy stores before they arrive at breeding sites, fast throughout the entire lactation period, which lasts from 4 to 50 days depending on the species. However, recent studies on harbor seals, a phocid species, found that lactating females commenced foraging approximately 6 days after giving birth and on average made 7 foraging trips during the remainder of their 24-day lactation period.
According to the passage, until recently zoologists believed which of the following about all phocid mothers?
- ATheir fasting periods after giving birth were typically shorter than those of otariids.
- BTheir lactation periods were generally as long as those of comparably sized otariids.
- CThey acquired only moderate energy stores in the form of blubber before arriving at breeding sites.
- DThey depleted less than a third of their stored body fat during lactation.
- EThe replenished their fat stores only after their lactation period ended.
显示答案
正确答案: E