This weed plays dead when touched or when it feels a source of heat.
Broadcast 26 January 1995, this episode examines how plants either share environments harmoniously or compete for dominance within them. Attenborough highlights the 1987 hurricane and the devastation it caused. However, for some species, it was that opportunity for which they had lain dormant for many years. The space left by uprooted trees is soon filled by others who move relatively swiftly towards the light. The oak is one of the strongest and longest-lived, and other, lesser plants nearby must wait until the spring to flourish before the light above is extinguished by leaves. Tropical forests are green throughout the year, so brute force is needed for a successful climb to the top of the canopy: the rattan is an example that has the longest stem of any plant. As its name suggests, the strangler fig ‘throttles’ its host by growing around it and cutting off essential water and light. Some can take advantage of a fallen tree by setting down roots on the now horizontal trunk and getting nutriment from the surrounding moss and the fungi on the dead bark. The mountain ash grows so tall, that regeneration becomes a considerable problem. It is easily inflammable, so its solution is to shed its seeds during a forest fire and sacrifice itself. It therefore relies on the periodic near-destruction of its surroundings in order to survive. Attenborough observes that catastrophes such as fire and drought, while initially detrimental to wildlife, eventually allow for deserted habitats to be reborn.
In this four-program series, string theory pioneer Michio Kaku goes on an extraordinary exploration of the world in search of time.
He discovers our sense of time passing and the clocks that drive our bodies. He reveals the forces of time that make and destroy us in a lifetime. He journeys to some of the Earth’s most spectacular geological sites to look for clues to the extraordinary depths of time at a planetary level. Finally, he takes us on a cosmic journey in search of the beginning (and the end) of time itself.
This powerful video illustrates how children imitate our every action. We are all examples for children to follow.
Excellent simple optical illusion using only a Charlie Chaplin mask. A distinguished elderly gentleman guides one through the effect and even adds philosophical observations relevant to real life, proving reality can be deceiving. Shows our mind can overtake reality. Present information can be overwritten by knowledge derived from the past.