Ecology. The Economy of Nature
9e édition

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Students report that Achieve makes it easy to engage with their coursework. Research shows that students using Achieve to get ready for class (completing at least 80% of their pre-class activities) can expect an 8% boost on their final exam scores. That's almost a full grade level higher ! ABOUT THE COVER PHOTO. A worker honeybee collecting nectar and pollen from Helenium flowers in Buckinghamshire, UK.
The workers are all female, and in most species they skip reproduction and help rear their siblings that are produced by a queen. However, in at least one subspecies that lives in South Africa, workers can lay diploid eggs without ever mating. Using an unusual form of meiosis, they produce haploid egg cells and then merge two haploid cells to form a diploid cell. As a result, a hive can persist without having a queen bee present for reproduction.
The wide range of reproductive modes in plants and animals is discussed in Chapter 8, Reproductive Strategies.