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There is one word of dialectical materialism： Motion is absolute ， while stillness is relative. Thousands of years ago， the ancient people moved out of Africa. After the population explosion and expansion， the 7 continents and 4 oceans were already full of human’s footprints. Until today， we are still fighting for migrating to other planets. This is the instinct of all living things to migrating. Not only people， animals are also experts to migrate. From the small invisible planktons to the large swimming whales， they all create great journeys， perform the wonderful drama of nature year after year， without rest for time and tide.
Birds——Fly for Living
Mentioning about migration， first of all， we think of birds. “As the autumn comes， a group of wild geese flies to the south， they form a ‘ren’ for a while， and form a ‘yi’ for another……” this is from the article we learned in the childhood， telling about our most familiar migratory birds. There is also record in the opening monologue of a movie：” this is a story about promise to come back. The birds fly ten thousands miles， experience trials and hardships， only for one purpose——survival. They fly for living.”
The migratory birds fly back to their born places to breed the next generation， and fly to the warm wintering ground with the newcomers in autumn. They repeat the processes， and never betray the promise. The smallest bird in the world is hummingbird， which is as small as a moth， they should also migrate with promise. Their small body contains large energy. They can cross more than 5000 kilometers from the born place——British Columbia in Canada （ the southwest of Canada） to the Mexican city. The female birds won’t set out at the same time with the male， for they should take care of the baby birds until they have enough flying abilities. As the exhausted physical power for breeding recover， they start the back journey with the new lives.
Insects——Pursuing for Food
Flying is not the birds’ patent， the insects fly in a splendid and magical journey. Butterflies are not just living things with gorgeous appearance， but also the practioners of migration’s practice. The monarch butterflies may be the most familiar butterflies for people and the only ones who take long distance migration in North America. These butterflies couldn’t resist the winter of Canada and the Northern America， their larva feed only on the plant asclepin， for the above two reasons， the monarch butterflies set out the journey from generation to generation. As we are marveling at the beauty of butterflies’ migration， another migratory insect may be extremely hated by us. Locusts， referring to the orthopteran in general， like to eat gramineous plants （ rice， wheat and so on）. They migrate for food， have many bad history. The locusts like warm and dry climate. So in the years of drought， especially in the seasons of extreme drought， the locusts bloom， its groups expand rapidly， and its need in food has an exponential increase. The small feeding ground cannot satisfy their bigger appetite， and they start the journey to search for new feeding ground. After the wreak havoc of overwhelming locusts， the farmland will have no harvest.
Fish——Call of Breeding
The eels live in the fresh water， after getting mature， they will swim downstream to the sea more than 5000 kilometers away to finish the only breeding in their lifetime. In the journey， their bodies change obviously， the color turns to silver gray which is more harmony to the sea， the head will get sharpen and more streamlined， the viscera will turn smaller. They stop eating， all the nutrition will be used to breed the millions of lives in the ovary. After laying eggs in the sea， the male eels and the female eels will die for exhaustion. But this is also the opening of new lives， the little eels begin to come out of the eggs and set out on the way back home. Without the guidance of parents， they have to experience hostile environment and natural enemies， swim back to the fresh water， then go upstream to where their parents grow up.
Minimals
——A Race of Survival
Africa（Savanna is the tropical grassland with few trees）. There are groups of cows， sheep and horses， they move for the water plants， which undoubtedly form the largest and most splendid migrations. The leading actor of the migration are mammals feeding on grass， there are about 2000 thousand gnus， 300 thousand zebras and 500 thousand gazelles. The Serengeti Plain of Tanzania is the gnus’ homeland， from every October to the next July， the gnus run wildly on this rich grassland. In October， they cross the Mara River， march from the Masai Mara Savanna to the south， and bear babies there. As March comes， they begin to march to the north of the Serengeti Plain. Before the June’s rainy season is over， they have reached the migration routine in the west. The real big migration for water and grass begins since then. In July， millions of gnus， no matter old or young， strong or weak， cross the Mara River again without hesitation， and march to the still rich Masai Mara Savanna far away. However， countless gnus die on the way， there are natural enemies like lions， cheetahs and wild dogs. The Mara River is also full of danger， many are drown or attacked by crocodiles and hippos. But this travel of promise about water and grass never stop. Amphibians
——The Promise
of Going Home
Each year， there are always several news with such a title——“ thousands of frogs go to the street， cause a panic of the residents”. Actually， this isn’t so-called “earthquake warning” in most cases， but the amphibians’ normal seasonal migration， like the frogs and toads. In the breeding season， the frogs will move from the rapid flowing river to the slow flowing river， lake or pond， for the environment is more fitting to lay eggs and be fertilized. Yet in the cold winter， some frogs may go to the hibernation area in groups.
These migrations are always in short distance， maybe only 1.5 to 3 kilometers. Compared to the animals travel for millions of kilometers， these are too small. Even though， it’s the promise which must be carried out every year. Another kind of animals who have the customary of hibernation are the reptiles， who also have different kinds of migration. The most famous are green turtles. They wander about in the sea throughout the year. Those spread in the Atlantic Ocean mainly find food in the near sea of Brazil. In the breeding season， groups of turtles swim for 2000 kilometers driven by the instinct， back to their born place——the small island called Ascension， then they lay eggs and hurry off. As the little turtles break the eggs and come out， they should struggle to crawl back to the sea with the tide， or they will die in the birds’ sharp claws if exposed for a long time on the beach.
These are stories about the promise in the animals’ migrations.
Birds——Fly for Living
Mentioning about migration， first of all， we think of birds. “As the autumn comes， a group of wild geese flies to the south， they form a ‘ren’ for a while， and form a ‘yi’ for another……” this is from the article we learned in the childhood， telling about our most familiar migratory birds. There is also record in the opening monologue of a movie：” this is a story about promise to come back. The birds fly ten thousands miles， experience trials and hardships， only for one purpose——survival. They fly for living.”
The migratory birds fly back to their born places to breed the next generation， and fly to the warm wintering ground with the newcomers in autumn. They repeat the processes， and never betray the promise. The smallest bird in the world is hummingbird， which is as small as a moth， they should also migrate with promise. Their small body contains large energy. They can cross more than 5000 kilometers from the born place——British Columbia in Canada （ the southwest of Canada） to the Mexican city. The female birds won’t set out at the same time with the male， for they should take care of the baby birds until they have enough flying abilities. As the exhausted physical power for breeding recover， they start the back journey with the new lives.
Insects——Pursuing for Food
Flying is not the birds’ patent， the insects fly in a splendid and magical journey. Butterflies are not just living things with gorgeous appearance， but also the practioners of migration’s practice. The monarch butterflies may be the most familiar butterflies for people and the only ones who take long distance migration in North America. These butterflies couldn’t resist the winter of Canada and the Northern America， their larva feed only on the plant asclepin， for the above two reasons， the monarch butterflies set out the journey from generation to generation. As we are marveling at the beauty of butterflies’ migration， another migratory insect may be extremely hated by us. Locusts， referring to the orthopteran in general， like to eat gramineous plants （ rice， wheat and so on）. They migrate for food， have many bad history. The locusts like warm and dry climate. So in the years of drought， especially in the seasons of extreme drought， the locusts bloom， its groups expand rapidly， and its need in food has an exponential increase. The small feeding ground cannot satisfy their bigger appetite， and they start the journey to search for new feeding ground. After the wreak havoc of overwhelming locusts， the farmland will have no harvest.
Fish——Call of Breeding
The eels live in the fresh water， after getting mature， they will swim downstream to the sea more than 5000 kilometers away to finish the only breeding in their lifetime. In the journey， their bodies change obviously， the color turns to silver gray which is more harmony to the sea， the head will get sharpen and more streamlined， the viscera will turn smaller. They stop eating， all the nutrition will be used to breed the millions of lives in the ovary. After laying eggs in the sea， the male eels and the female eels will die for exhaustion. But this is also the opening of new lives， the little eels begin to come out of the eggs and set out on the way back home. Without the guidance of parents， they have to experience hostile environment and natural enemies， swim back to the fresh water， then go upstream to where their parents grow up.
Minimals
——A Race of Survival
Africa（Savanna is the tropical grassland with few trees）. There are groups of cows， sheep and horses， they move for the water plants， which undoubtedly form the largest and most splendid migrations. The leading actor of the migration are mammals feeding on grass， there are about 2000 thousand gnus， 300 thousand zebras and 500 thousand gazelles. The Serengeti Plain of Tanzania is the gnus’ homeland， from every October to the next July， the gnus run wildly on this rich grassland. In October， they cross the Mara River， march from the Masai Mara Savanna to the south， and bear babies there. As March comes， they begin to march to the north of the Serengeti Plain. Before the June’s rainy season is over， they have reached the migration routine in the west. The real big migration for water and grass begins since then. In July， millions of gnus， no matter old or young， strong or weak， cross the Mara River again without hesitation， and march to the still rich Masai Mara Savanna far away. However， countless gnus die on the way， there are natural enemies like lions， cheetahs and wild dogs. The Mara River is also full of danger， many are drown or attacked by crocodiles and hippos. But this travel of promise about water and grass never stop. Amphibians
——The Promise
of Going Home
Each year， there are always several news with such a title——“ thousands of frogs go to the street， cause a panic of the residents”. Actually， this isn’t so-called “earthquake warning” in most cases， but the amphibians’ normal seasonal migration， like the frogs and toads. In the breeding season， the frogs will move from the rapid flowing river to the slow flowing river， lake or pond， for the environment is more fitting to lay eggs and be fertilized. Yet in the cold winter， some frogs may go to the hibernation area in groups.
These migrations are always in short distance， maybe only 1.5 to 3 kilometers. Compared to the animals travel for millions of kilometers， these are too small. Even though， it’s the promise which must be carried out every year. Another kind of animals who have the customary of hibernation are the reptiles， who also have different kinds of migration. The most famous are green turtles. They wander about in the sea throughout the year. Those spread in the Atlantic Ocean mainly find food in the near sea of Brazil. In the breeding season， groups of turtles swim for 2000 kilometers driven by the instinct， back to their born place——the small island called Ascension， then they lay eggs and hurry off. As the little turtles break the eggs and come out， they should struggle to crawl back to the sea with the tide， or they will die in the birds’ sharp claws if exposed for a long time on the beach.
These are stories about the promise in the animals’ migrations.