Section 2 Relationship Between the Earth's Environment and Living
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Section2 Relationship between the Earth's Environment and Living Organisms out the relationship between snails and a kind of miss capture of the snails when the snake is given snake whose predation is specialized to snails. The sinistral snails. This works as an advantage to report shows that the specialized snake predation sinistral snails, and as a result, many sinistral drives prey (snail) speciation. Snail Eating Snake snails can be observed in regions where the Snail- (Pareas iwasakii), which is specialized predator of Eating Snakes is distributed. snails, is distributed broadly from the Yaeyama According to the Ministry of the Environment’s Islands of Okinawa to southern China, India, and Red List, approximately 30% of terrestrial Molluscan Southeast Asia. This snake has specialized its jaw species, including snails, are endangered due to Chapter 2 Healthy Interaction between Human and the Earth to eat dextral (clockwise coiled) snails, because human activities such as logging forests and many snails are clockwise coiled. This speciation developing land in their habitats, as their means of causes sinistral (counterclockwise coiled) snails movement is crawling over the ground on their survive predation by the snake: the snake tends to bellies and this is a barrier for their survival. Pareas Snake Preying on a Snail 5mm 5mm Successful predation of a right-coiled shell Failed predation of a left-coiled shell The numbers of teeth differ between the left and right sides of the jaw. Source: Hoso, M., Kameda, Y., Wu, S. P., Asami, T., Kato, M. & Hori, M.（2010） A speciation gene for left-right reversal in snails results in anti-predator adaptation Photographs provided by Masaki Hoso Section 2 Relationship between the Earth’s Environment and Living Organisms In Section1 we looked at the close relationship between ecosystems and living organisms. our everyday lives and biodiversity. Our everyday lives Here focusing on dynamic migration of birds and fish depends on biodiversity, and the biodiversity is depend and dispersal of animals, we will discus the relationship on keeping the living organisms and the ecosystems in between ecosystems and organisms in order to understand good health and preserving the interaction between those it. 1. The Relationship between Organisms and the Earth （1）The Flyway - Crossing in the Sky autumn. These ducks take a rest of their wings in lakes on their way to the south of Japan, feeding themselves. In the Heian Period (8th to 12th Century), Sei Shonagon, And they pass the winter in south regions of Japan. who was a court lady to Empress around year 1000, Here we will look at this migration through the trend wrote “The Pillow Book” (in Japanese “Makura no in number of Pintails that fly to wetlands in Japan. The Sōshi”): “In autumn evenings...more charming still is a number of Pintails in Hokkaido reaches a peak around file of wild geese, like specks in the distant sky.” This December. After that they fly to the south, and there are expresses the sight of aquatic birds migrating over Japan hardly few Pintails in Hokkaido’s Lake Furenko. Large before winter comes, which has an aesthetic of autumn. In number of Pintails pass the winter in Japan’s southern recent years, the migrating route of some bird species areas. After they leave for the north before spring, they has been coming clearly due to the development of bird are no longer seen in the places where they passed the banding surgery, and tracking study technology that uses winter. In spring, reaching a peak around April for satellites to ducks and hawks. For example, Wigeon and crossing Hokkaido again, almost none remain in Japan Pintail, which can be seen in large numbers across Japan around May (Figure 2-2-1). from autumn to winter, breed in Russia’s Kamchatskaya Aquatic birds thus use wetlands not by staying in a Peninsula in the summer and then fly to Hokkaido in single place but instead use them like stepping stones. 41 FY2010 Part 1, Chapter 2 －Healthy Interaction between Human and the Earth Figure 2-2-1 Migration Routes for Pintails and Anas Penelopes; and Shifts in the Number of Pintails that Come, by Location June 16 - Oct. 12 Pintail Legend Wigeon a Wigeon b Pintail May 31 Nov. 6 June 8 July 9 - Sept. 18 Nov. 7 June 7 June〜 7 May 30 June 12 June 28 Oct. 14 Oct. 28 June 5 Wigeon Nov. 5 May 12 May 25 Oct. 4 Nov. 1 5000 Number of birds that come May 15 Oct. 3 Nov. 2 4500 April 24 3500 May 29 2500 April 19 2000 March 28 - May 13 1 1500 1000 April 12 2 500 3 0 910111212345 April 11 （Month） 4 ❶Furen-ko ❷Kominato April 9 March 9 ❸Abukuma River ❹Nagahamakantaku Nishidadozaka Source: Ministry of the Environment's Study on the State of Bird Migration (FY2009) and Report on Study to Clarify Bird Migration Routes (FY2007) Each of the wetlands plays an important role for aquatic Figure 2-2-2 Commonality Between Japan’s birds to rest their wings. This interaction of wild bird habitats through the flyway is referred to as a “flyway Mammals and Neighboring Regions network,” meaning an interaction of habitats through Similar species with their flight path. Because this flyway network can be a eastern Russia 41％ borderless interaction on a global-scale, it is an important ecosystem network internationally. （2）Diversity of Species Due to Dispersal and Geographic Isolation Similar species with the Korean Peninsula 34％ The Japanese archipelago in the glacial age differed Similar species with from today, because it geographically connected to the mainland China 40％ Eurasia. At that time, various living organisms moved into the Japanese archipelago from Taiwan in the south and the Korean Peninsula and Sakhalin in the north. Many of the mammals and other living organisms that can be seen in Japan today are descendents of the living organisms that came to Japan in the glacial age (Figure 2-2-2). Similar species with Those living things were distributed widely across the Taiwan 12％ Japanese archipelago, but they were blocked by the deeply cut Tokara Strait. This geographic isolation Similar species with Southeast Asia 9％ causes the difference of species distribution between the north and south of that strait. In the case of Japan, this appears especially in the diversity and distribution of amphibians. 40 species and subspecies of frogs are distributed in Japan. Almost all Source: Ministry of the Environment's“Japan's Biodiversity - Coexistence of Nature and People” of them are distributed either south of the Amami Islands or north of the Tokara Archipelago, and only a few Strait. For example, the black-spotted pond frog and the species are distributed on both sides of the Tokara Japanese brown frog, which are distributed north of the 42 Section2 Relationship between the Earth's Environment and Living Organisms Tokara Archipelago, cannot be seen south of the Amami approximately 80% are endemic to Japan. This is the Islands, and the same species and allied species inhabit eleventh highest ratio in the world (Figure 2-2-4). the Far East, the Korean Peninsula, and northern China. Meanwhile, species distributed south of the Amami （3）The Vast Interaction between Forests Islands cannot be seen north of the Tokara Archipelago, and the Sea including in Honshu, and most of their allied species are distributed from the southeast portion of China through Nutrients flow from forests into the sea through Southeast Asia (Figure 2-2-3). rivers. In the sea, phytoplankton and seaweed grow by Chapter 2 Healthy Interaction between Human and the Earth Organisms that have been geographically isolated using those nutrients. This phytoplankton and seaweed are separated into other species after many years have becomes food for zooplankton, small fish and shellfish, passed. The 5 species of Okinawa tip-nosed frog, which and these small living organisms are consumed by bigger are distributed in islands south of the Amami Islands on fish. The fish and shellfish are used as food by birds and the Ryukyu Archipelago, were isolated approximately humans. In this way, it is possible to think that ocean and 8.7 million years ago. They were separated from their land are connected ecosystems. This ocean-land continental ancestors because the sea level rose after the interaction is sometimes expressed by the phrase “the last glacial age, and then after approximately 7 million forest is the ocean’s sweetheart.” years they separated into 5 species such as the Amami This kind of interaction is not only the forests and the tip-nosed frog (Rana amamiensis) and Utsunomiya’s tip- sea, but also at the borders of ocean and land there are nosed frog (Rana utsunomiyaorum) and so on, which are sandy beaches and rocky shores, and a wide variety of endemic species of the Ryukyu Archipelag. In addition, organisms inhabit the area. Tidal flats and seaweed beds in the Ornate narrow-mouthed frog (Microhyla ornate), are particularly rich in organisms and have high water which is an endemic species of the Ryukyu Archipelago, purification capacity. The amount of production of extremely large genetic differences have been identified organisms in such coastal areas is extremely abundant, on each of the islands in the Ryukyu Archipelago. This and the juvenile fish are grown in these areas. is thought that the Ornate narrow-mouthed frog is A large-scale example of the ocean-land interaction is separating into different species on each island in the Amur River and the ocean. Nutrients flow out of the Ryukyu Archipelago. Amur River into Sea of Okhotsk and are carried by the A characteristic of the amphibians in Japan is that dense and cold flow of seawater that occurs when the sea many of them are endemic species.