Adaptations: Coniferous forests

This is a forest in northern Sweden. Let's take a look at the trees that are growing here... They have needles, and bear no fruit or flowers. These trees are called conifers, and this forest is called a coniferous forest. Conifers can grow around the world, but these coniferous forests are mostly found in the Northern Hemisphere, as far north as the Arctic Circle.

In this part of the world, temperatures are often very cold. And so, the plant and animal life in these forests have adapted. As you have already noticed, one of the most notable adaptations of conifers is their needles. These are actually small, tightly packed leaves. Their flat and narrow shape reduces the surface area of the leaf, which in turn reduces the amount of water the leaf loses through evaporation.

The needles also usually have a thick, waxy coating that guards against water loss and freezing. This helps conifers survive long dry periods. But… these needles also have a downside: because they are small, they are not very good at capturing sunlight and making nutrients for the tree. This means that most conifers can’t produce enough energy to drop their needles every autumn and regrow them in the spring, like many other trees do. Instead, they conserve energy by keeping their needles for two or three years, and replace them gradually over time.

This means that the majority of conifers maintain a dark green colour all year. You may notice that many conifers have a cone-like shape - narrower on the top and broader on the bottom. Thanks to this adaptation, snow can easily slide down to the ground, instead of collecting on the branches and weighing them down. It also ensures that higher branches do not cast shade on the branches below. This helps the tree get enough light, especially during the dark winter months.

If conifers don't have fruit or flowers, how do they produce seeds? Rather than growing flowers, conifer seeds develop inside cones. These cones keep seeds safe from animals and the weather. Pine cones, for example, are hard and woody, with special scales that stay tightly closed when it’s very cold and damp. When the weather is hot and dry, the pinecone scales open, allowing seeds to escape.

The cone of this juniper tree looks quite different – more like a berry than a pine cone! This is another adaptation some conifers have to attract birds to eat the seeds inside and disperse them. To cope with the winter cold, animals in coniferous forests adapt in different ways. Some animals such as bears, enter a dormant state during the winter — they hibernate. This way they can conserve energy when food is scarce.

The lack of food in the coniferous forest in the winter, causes many bird species to leave, migrating somewhere warmer. Crossbills, however, are one example of a bird that is well-adapted to living in the coniferous forest all year long. Crossbills have unique beaks where the upper and the lower parts completely overlap each other. While this looks somewhat odd, it serves an important purpose: it allows the crossbill to pry open coniferous cones to eat the seeds inside! Many animals in coniferous forests hibernate… migrate… and develop physical adaptations.

Coniferous trees meanwhile, have needles that they keep for many years, grow in conical shapes, and store their seeds in cones.