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  • A competitive environment: a dense stand of Himalayan Balsam (Impatiens glandulifera).

    Competitive neighbours? That may depend on who they are….

    Plants most often live side-by-side with other plants. Neighbours compete locally with one another for light, water and soil nutrients. An individual plant may find itself alongside members of other species, “strangers” of its own species, or its own close kin (parents, offspring or siblings). There are two main schools of thought on how related […] More

  • Marchantia polymorph

    When the going gets tough….. the organelles get going

    Chloroplasts, the tiny photosynthetic energy factories of plant cells, were observed to move in response to light and temperature as long as a century ago. Within a cell, these organelles can migrate towards the cell wall closest to a light source, thereby optimising photosynthesis. They do, however, move away from very strong light, presumably to […] More

  • A fossil flowe

    Dead End Street: Is self-fertilisation the end of the road for flowering plants?

    One of the basic and most widely accepted hypotheses in plant breeding systems is that flowering plant species that embrace self-fertilisation enter an evolutionary “dead end”, and are destined for extinction. The theory is based on the assumptions that it is impossible for species that exclusively self-pollinate to return to outcrossing, and that in such […] More

  • in

    Succulent plants of Africa and America: Do these lookalikes live alike?

    There are numerous examples in nature of distantly-related organisms converging on similar shapes that have proved useful to each. This convergent evolution can generate strikingly similar but independently evolved forms such as the streamlined bodies of dolphins and ichthyosaurs (a group of extinct marine reptiles); the wing shapes of birds and bats and the similar […] More

  • A female and male mandrake

    Gender inequality (in plant populations). What causes unequal numbers of males and females?

    Populations of dioecious flowering plants (which have male and female individuals) often depart from the expected male:female ratio of 1:1. The causes of skewed sex ratios are complex and still poorly understood. As with many species that have two sexes, females must invest more resources in reproduction. In the case of flowering plants, this is […] More