Fourth 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 (eucalyptus regnans) grows so tall, that regeneration becomes a considerable problem. It is easily flammable, 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.

Take a look back at many of the most fascinating science stories of 2017, a year full of stunning advancements in individual fields of study, from astronomy to biology, geology to history – when we piece these discoveries together we see the year in a new light.

As NASA releases the first images from the James Webb Space Telescope, this film tells the inside story of the telescope's construction and the astronomers taking its first picture of distant stars and galaxies. Will it be the deepest image of our universe ever taken? The successor to Hubble, and 100 times more powerful, the James Webb is the most technically advanced telescope ever built. It will look further back in time than Hubble to an era around 200 million years after the Big Bang, when the first stars and galaxies appeared. Webb's primary mission is to capture the faint light from these objects on the edge of our visible universe so that scientists can learn how they formed, but its instruments are so sensitive it could also be the first telescope to detect signs of life on a distant planet.
The James Webb Telescope is an £8 billion gamble on the skills of its engineering team. It’s the first telescope designed to unfold in space – a complicated two-week operation in which 178 release devices must all work - 107 of them on the telescope's sun shield alone. If just one fails, the expensive telescope could become a giant piece of space junk.
From its conception in the late 1980s, the construction of Webb has posed a huge technical challenge. The team must build a mirror six times larger than Hubble’s and construct a vast sun shield the size of a tennis court, fold them up so they fit into an Ariane 5 rocket, then find a way to unfold them in space. This film tells the inside story of the James Webb Space Telescope in the words of the engineers who built it and the astronomers who will use it.

It's a universal dream To soar on wings into the heavens. But it's nothing compared to the reality. Experience our planet as never before: Through the eyes of birds. This is a journey that will embrace the world. A flight across the earth on feathered wings. It's a fantastic voyage following the changing seasons and taking in some of the greatest events on Earth.
Experience a year in the life of our planet from the lush tropics to the frozen North and catch a glimpse of our world as never before: From a bird's-eye view.

In the third episode of the series, Steven is back in jail, charged with murder, but there are troubling questions about how he was arrested and why.

Across the universe, galaxies are going dark, and scientists don't know why the stars are losing their shine. Something is slowly drawing the curtains closed on the universe. Our milky way is under threat. Astronomers race against time to uncover the truth behind how galaxies are born and how they die before all of the lights go out.