Bananas, apples and avocados are called climacteric fruits because they continue to become ripe after they are picked. Cherries, blackberries and grapes are called non-climacteric fruits because they do not. Knowing the difference between them is pivotal for fruit-growers and greengrocers because they can keep their goods in perfect condition when they arrive at the market places based on the knowledge. But how the difference originally came about remains unclear.
Fukano Yuya and Tachiki Yuuya of the University of Tokyo offered a view. Fruits, which they observe, exist to solve a problem faced by all plants-how to best spread their young around. Wrapping their seeds in the sugary fruits, to provide a tasty meal, serves as a way to get animals to do this for them. They do, however, need to make sure that their fruits favour the animals most likely to do the distribution work. Their climacterism, or its absence, is a way to achieve this.
To test their idea, the two researchers looked into 276 papers reporting on 80 sorts of fruits, and noted which animals each depended on for the distribution of their young 35 of these fruits they discovered, were eaten by both ground-dwelling animals and those living above the ground. But of others, 15 of the 19 eaten mainly by ground dwellers were climacteric, while 21 of the 26 fed on by animals living above the ground were non-climacteric.
That is a suggestively strong connection. Other evidence points out that non-climacteric fruits tend to have vivid colors. This may help them stand out amid the leaves of their parent plants, advertising their presence. On the contrary, climacteric fruits are generally better at hiding themselves. That makes them harder to spot until they have fallen to the ground.
The main limitation of their work, say Dr Fukano and Dr Tachiki, is that most of the papers they looked through concerned fruits eaten by people. This has probably affected, the sample, for thousands of years of selective breeding for characteristics that human beings find attractive may have weakened any signal improved by natural selection. The next step, therefore, should probably be to limit the analysis to wild fruits.
12. What does the underlined word “pivotal” in paragraph 1 probably mean?
A.Critical | B.Popular | C.Reasonable | D.Obvious. |
13. How do plants spread seeds according to Fukano and Tachiki?
A.By using their fruits to protect their seeds. |
B.By showing their sugary seeds to attract animals. |
C.By hiding their seeds on animals’favorite plants. |
D.By making their fruits beneficial to the potential spreaders. |
14. Which can best describe the non-climacteric fruits?
A.Protective and fully-grown. | B.Small-sized and unnoticeable. |
C.Bright-colored and eye-catching. | D.Hard and eaten by ground dwellers. |
15. What do Dr Fukano and Dr Tachiki aim to do in the future?
A.Find out fruits of old varieties. | B.Turn to the study of wild fruits. |
C.Look into the selective breeding fruits. | D.Protect different fruit plants for breeding. |