Saturday, October 27, 2007
Tuesday, October 23, 2007
Habitats and Adaption
Habitat and Adaptation
© WWF-Canon / Roger LeGuen
Every organism has a unique ecosystem within which it lives. This ecosystem is its natural habitat. This is where the basic needs of the organism to survive are met: food, water, shelter from the weather and place to breed its young. All organisms need to adapt to their habitat to be able to survive.
This means adapting to be able to survive the climatic conditions of the ecosystem, predators, and other species that compete for the same food and space. An adaptation is a modification or change in the organism's body or behaviour that helps it to survive. Explore the links given here to know more about habitats and how different plants and animals.
An animal may adapt to its habitat in different ways. It may be a physical or structural adaptation, just as the limbs of birds have modified into wings or the way the cheetah is shaped for running at a fast speed.
It may be in the way the body works in circulating and respiration, for instance the gills that fish have enable them to breathe in water. Or it may be the way the animal behaves whether it is hunting for food, or running fast to avoid predators or migrating to other places for food or survival. To know more about different types of adaptations visit the link.
An animal's environment consists of many different things. The climate, the kinds of food plants that grow in it, other animals that may be predators or competitors- the animal must learn to adapt to each of these factors in order to survive. With increasing population growth and human activity that disturbs the natural habitat, animals must learn to adapt to these kind of threats as well.
Animals in the wild can only live in places they are adapted to. They must have the right kind of habitat where they can find the food and space they need. Visit the link for a brief overview of how animals adapt to their habitat.
Did you know that animals camouflage themselves so they can adapt to their environment? Adaptation can protect animals from predators or from harsh weather. Many birds can hide in the tall grass and weeds and insects can change their colour to blend into the surroundings. This makes it difficult for predators to seek them out for food.
Some animals, like the apple snail, can survive in different ecosystems- from swamps, ditches and ponds to lakes and rivers. It has a lung/gills combination that reflects its adaptation to habitats with oxygen poor water. This is often the case in swamps and shallow waters. To know more about how the apple snail can survive in different habitats visit the link.
In the harsh cold climate of Alaska, the animals have learnt to adapt to the weather by storing food in their body and protecting themselves from the cold with thick furs. Human inhabitants in Alaska have also learnt to cope with the environment by building shelters that insulate and hold the heat, and yet do not allow the structure to melt.
Plants Habitates
Where the Flowers Grow
Alaska is the largest of the 50 states. Elevations range from sea level to the top of Mt. McKinley, the highest peak in North America. Because of Alaska's size and varied elevations, growing conditions are very different. The amount of snow, how severe the winter is, and when the snow melts, determines the blooming time of the plants in that particular area. If you take a plant out of its' environment it may not grow. Climate has a lot to do with where a plant grows.
There are three main habitats that plants grow in, although, there is a space of transition in each one where habitat features overlap. For the sake of simplicity, Alpine is defined as above treeline and often having scree slopes, Sub-Alpine, below Alpine with some trees and many low shrubs, and lowlands, which is tree line and below with many varieties of plants and tall trees.
Plants in Alpine are slow growing and low to the ground. They are slow growing because to get to a source of water, they must grow their taproot first. It sometimes takes five years for a flower to grow to the size of a half dollar. By this time the taproot is about 10 to 12 inches long. Flowers in this area grow close to rocks on scree slopes. The rocks protect them from high winds, and are a source of
. In a picture, I saw one flower even turned toward a rock, maybe because it confused it for the sun. You are likely to see the Chocolate Lily, Triangular Leafed Fleabane, Nootka Lupine, Wooly Lousewort, and Mountain Forget-Me-Nots in this habitat.
Shrubs, herbs and small plants grow in Sub-Alpine habitats. You will find Salmonberry, Devil's Club, Wild Currents, Tundra Rose, Pasque Flower, and Prickly Rose here. In areas where the shrubs are thick, the taller ones will block out the much needed sun. In these places you will find plants that grow before the leaves appear on the trees or can grow in the shade. In the woodsy areas, fire is the biggest danger to plants. It takes many years for plants to grow back after a fire.
Below Alpine and Sub-Alpine are the Lowlands. There are thick forests in this region so fire is still a big danger to these plants. Along the coast the plants are hugely affected by the saltwater. Most coastal wetlands have silt, sand, and in restricted areas, gravel. These along with the tide, prevent plants from becoming well rooted. Lowlands also consist of woodlands, meadows, swamps, marshes, and shallow open water. In these areas you will find Pond Lillies, Bluebells of Scotland, Wild Iris and Fireweed to name a few.
The Plant Life Cycle
The Life Cycle
When a seed falls to the ground it starts what is often referred to as The Life Cycle. Once in the ground the seed needs water and warmth to start the next step in growth called germination. Germination is when the seed swells taking in water and nutrients and starts to grow. After the germination process has started the seed forms a root that will search for food and water in the soil to help the seed grow. With heat and moisture the seed starts to form it's first leaves underground. The sprout needs to get those leaves to the surface to absorb more food and to grow, so the sprout pushes up as the roots grow downward. The root now forms tiny lateral roots. Next the cotyledon forces upwards protecting the tender leaves between them. The leaves are referred to as plumule leaves. When the leaves are up out of the ground they open and start to make food for the plant from oxygen and light. This is called photosynthesis. The cotyledons are not needed any more so they wither and fall off. The leaves grow and the stem starts to stretch upward. This stage of growth takes quite a while in some plants. The root system grows downward and outward to provide a foundation for the growing plant. After a while a bud starts to form. Inside the bud a flower forms. The bud consists of many layers of flower parts. When they are fully formed the flower opens up and the true beauty inside is revealed and their scent is released. This attracts butterflies, bees, flies, and other insects that aid in pollination from flower to flower. Once pollinated, the seeds can ripen and be distributed by the wind and other animals eating them and thus carrying them to other places. Seeds can even explode out of the seed pods! Once the seeds are in different places, the life cycle continues once again.
General Things About Plants
Most people do not recognize the importance of plants, when in fact plants play an influential part in our daily lives. Plants take in carbon dioxide and give out oxygen which we breathe in. Without plants, we would not have clean air to breathe!
Plants grow in every region of the world. Heat, light, and water are basic essential needs for all except the simplest types of plants. Most flowers can't thrive without pollination, one way pollination is done is by insects, mainly by bees, butterflies, and fruitflies. Pollination is when pollen from the anther is transferred to the stigma to make seeds.
Some flowers do not need pollination to produce seeds for reproduction, their roots are designed to reproduce on their own. There are several kinds of roots that reproduce, rhizomes, stolons, bulbs, runners, corms, and tubers. Because of Alaska's short summers a lot of wild flowers reproduce in this way. Rhizomes are underground stems that grow just under the surface of the soil where every so often a flower shoots up. Alaska's blue irises reproduce this way. A corm resembles small underground leaves wrapped around each other similar to an onion, that new corms grow from. A bulb is similar to a corm but reproduces in the same place each year without moving. A tuber is a big group of swollen stems that act as a storage chamber, each of which can form a new plant after the main plant has died. A runner is sent above ground and roots grow out to anchor the new plant. All strawberries can reproduce this way.
Monday, October 22, 2007
DASA
