The second species, A．suarezensis, had a higher estimated current population of 15,000 trees but a far smaller distribution area of just 1,200 square kilometers. Based on climate change models, the researchers estimated that the distribution of this species will cover just 17 square kilometers by 2050 and could face potential extinction by 2080.

　　The one bright spot in their study was A．grandidieri, the largest and most populous baobab species. The researchers counted an estimated one million trees with a distribution of more than 26,000 square kilometers. This isn't expected to change much by 2050.

　　As the researchers point out, there's nowhere left for the baobabs to go. Many baobab trees currently are in Protected Area Networks (PANs) established to preserve Madagascar's biodiversity, but the areas outside many PANs have been almost completely changed to agriculture or cattle feeding areas, leaving no room for the trees to expand their distribution.

　　The researchers wrote that the existing PAN system in Madagascar “is not likely to be effective for biodiversity conservation in the future” because the PANs will not always contain the ecological features necessary for the survival of the species that live inside them today. They suggest that the PAN system will need to be adapted.

　　1．According to the text, baobab trees ________.

　　A．don't bear fruits

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