{"id":3206,"date":"2017-02-10T22:35:23","date_gmt":"2017-02-10T22:35:23","guid":{"rendered":"https:\/\/courses.lumenlearning.com\/wm-biology2\/?post_type=chapter&#038;p=3206"},"modified":"2024-04-26T02:47:50","modified_gmt":"2024-04-26T02:47:50","slug":"biogeography-and-species-distribution","status":"publish","type":"chapter","link":"https:\/\/courses.lumenlearning.com\/wm-biology2\/chapter\/biogeography-and-species-distribution\/","title":{"raw":"Biogeography and Species Distribution","rendered":"Biogeography and Species Distribution"},"content":{"raw":"<div class=\"textbox learning-objectives\">\r\n<h3>Learning Outcomes<\/h3>\r\n<ul>\r\n \t<li>Define the term biogeography and the abiotic factors that impact it<\/li>\r\n \t<li>Discuss how abiotic factors affect species distribution<\/li>\r\n<\/ul>\r\n<\/div>\r\n<p id=\"fs-idp8923504\"><strong><span id=\"term2204\" data-type=\"term\">Biogeography<\/span><\/strong>\u00a0is the study of the geographic distribution of living things and the\u00a0<em data-effect=\"italics\">abiotic fact<\/em>ors that affect their distribution. Abiotic factors such as temperature and rainfall vary based mainly on latitude and elevation. As these abiotic factors change, the composition of plant and animal communities also changes. For example, if you were to begin a journey at the equator and walk north, you would notice gradual changes in plant communities. At the beginning of your journey, you would see tropical wet forests with broad-leaved evergreen trees, which are characteristic of plant communities found near the equator. As you continued to travel north, you would see these broad-leaved evergreen plants eventually give rise to seasonally dry forests with scattered trees. You would also begin to notice changes in temperature and moisture. At about 30 degrees north, these forests would give way to deserts, which are characterized by low precipitation and high insolation (sunlight).<\/p>\r\n<p id=\"fs-idm116523360\">Moving farther north, you would see that deserts are replaced by grasslands or prairies. Eventually, grasslands are replaced by deciduous temperate forests. These deciduous forests give way to the boreal forests and taiga found in the subarctic, the area south of the Arctic Circle. Finally, you would reach the Arctic tundra, which is found at the most northern latitudes. This trek north reveals gradual changes in both climate and the types of organisms that have adapted to environmental factors associated with ecosystems found at different latitudes. However, different ecosystems exist at the same latitude due in part to abiotic factors such as jet streams, the Gulf Stream, and ocean currents. If you were to hike up a mountain, the changes you would see in the vegetation would parallel in many ways those as you move to higher latitudes.<\/p>\r\n<span style=\"color: #077fab; font-size: 1.15em; font-weight: 600;\">Species Distribution<\/span>\r\n\r\nEcologists who study biogeography examine patterns of species distribution. No species exists everywhere; for example, the Venus flytrap is endemic to a small area in North and South Carolina. An <strong>endemic<\/strong> species is one which is naturally found only in a specific geographic area that is usually restricted in size. Other species are generalists: species which live in a wide variety of geographic areas; the raccoon, for example, is native to most of North and Central America.\r\n\r\nSpecies distribution patterns are based on biotic and abiotic factors and their influences during the very long periods of time required for species evolution; therefore, early studies of biogeography were closely linked to the emergence of evolutionary thinking in the eighteenth century. Some of the most distinctive assemblages of plants and animals occur in regions that have been physically separated for millions of years by geographic barriers. Biologists estimate that Australia, for example, has between 600,000 and 700,000 species of plants and animals. Approximately 3\/4 of living plant and mammal species are endemic species found solely in Australia (Figure\u00a01).\r\n\r\n[caption id=\"attachment_3223\" align=\"aligncenter\" width=\"1024\"]<img class=\"size-large wp-image-3223\" src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/1223\/2017\/02\/10224509\/Figure_44_02_01ab-1024x558.jpg\" alt=\" Photo (a) depicts a wallaby, a member of the kangaroo family. The wallaby is brown with white flecks on its fur and a light brown underbelly. Its hands are clasped together. Photo (b) shows an echidna. Like a porcupine, the echidna has a compact body covered with brown and white quills. It has a long, slender snout.\" width=\"1024\" height=\"558\" \/> Figure 1. Australia is home to many endemic species. The (a) wallaby (Wallabia bicolor), a medium-sized member of the kangaroo family, is a pouched mammal, or marsupial. The (b) echidna (Tachyglossus aculeatus) is an egg-laying mammal. (credit a: modification of work by Derrick Coetzee; credit b: modification of work by Allan Whittome)[\/caption]\r\n\r\nSometimes ecologists discover unique patterns of species distribution by determining where species are <em>not<\/em> found. Hawaii, for example, has no native land species of reptiles or amphibians, and has only one native terrestrial mammal, the hoary bat. Most of New Guinea, as another example, lacks placental mammals.\r\n<div class=\"textbox\">\r\n\r\nCheck out this video to observe a platypus swimming in its natural habitat in New South Wales, Australia. Note that this video has no narration.\r\n\r\n[video width=\"640\" height=\"480\" mp4=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/1223\/2017\/04\/13160921\/6822054037_sd.mp4\"][\/video]\r\n\r\n<\/div>\r\nLike animals, plants can be endemic or generalists: endemic plants are found only on specific regions of the Earth, while generalists are found on many regions. Isolated land masses\u2014such as Australia, Hawaii, and Madagascar\u2014often have large numbers of endemic plant species. Some of these plants are endangered due to human activity. The forest gardenia (<em>Gardenia brighamii<\/em>), for instance, is endemic to Hawaii; only an estimated 15\u201320 trees are thought to exist (Figure 2).\r\n\r\n[caption id=\"\" align=\"aligncenter\" width=\"351\"]<img id=\"5\" class=\"\" src=\"https:\/\/openstax.org\/resources\/c09285b9cd10fd5ac4a92b823f9559a7319461a2\" alt=\"The photo shows a white flower with seven smooth, diamond-shaped petals radiating out from a yellow center. The flower is surrounded by waxy green leaves.\" width=\"351\" height=\"315\" data-media-type=\"image\/jpg\" \/> Figure 2. Listed as federally endangered, the forest gardenia is a small tree with distinctive flowers. It is found only in five of the Hawaiian Islands in small populations consisting of a few individual specimens. (credit: Forest &amp; Kim Starr)[\/caption]\r\n\r\n&nbsp;\r\n<div class=\"textbox tryit\">\r\n<h3>Try It<\/h3>\r\nhttps:\/\/assess.lumenlearning.com\/practice\/5d4f0972-5c8e-4058-9e3b-913abe2e8a23\r\nhttps:\/\/assess.lumenlearning.com\/practice\/623076b4-2195-4b95-b5c1-e30af5922508\r\n<\/div>","rendered":"<div class=\"textbox learning-objectives\">\n<h3>Learning Outcomes<\/h3>\n<ul>\n<li>Define the term biogeography and the abiotic factors that impact it<\/li>\n<li>Discuss how abiotic factors affect species distribution<\/li>\n<\/ul>\n<\/div>\n<p id=\"fs-idp8923504\"><strong><span id=\"term2204\" data-type=\"term\">Biogeography<\/span><\/strong>\u00a0is the study of the geographic distribution of living things and the\u00a0<em data-effect=\"italics\">abiotic fact<\/em>ors that affect their distribution. Abiotic factors such as temperature and rainfall vary based mainly on latitude and elevation. As these abiotic factors change, the composition of plant and animal communities also changes. For example, if you were to begin a journey at the equator and walk north, you would notice gradual changes in plant communities. At the beginning of your journey, you would see tropical wet forests with broad-leaved evergreen trees, which are characteristic of plant communities found near the equator. As you continued to travel north, you would see these broad-leaved evergreen plants eventually give rise to seasonally dry forests with scattered trees. You would also begin to notice changes in temperature and moisture. At about 30 degrees north, these forests would give way to deserts, which are characterized by low precipitation and high insolation (sunlight).<\/p>\n<p id=\"fs-idm116523360\">Moving farther north, you would see that deserts are replaced by grasslands or prairies. Eventually, grasslands are replaced by deciduous temperate forests. These deciduous forests give way to the boreal forests and taiga found in the subarctic, the area south of the Arctic Circle. Finally, you would reach the Arctic tundra, which is found at the most northern latitudes. This trek north reveals gradual changes in both climate and the types of organisms that have adapted to environmental factors associated with ecosystems found at different latitudes. However, different ecosystems exist at the same latitude due in part to abiotic factors such as jet streams, the Gulf Stream, and ocean currents. If you were to hike up a mountain, the changes you would see in the vegetation would parallel in many ways those as you move to higher latitudes.<\/p>\n<p><span style=\"color: #077fab; font-size: 1.15em; font-weight: 600;\">Species Distribution<\/span><\/p>\n<p>Ecologists who study biogeography examine patterns of species distribution. No species exists everywhere; for example, the Venus flytrap is endemic to a small area in North and South Carolina. An <strong>endemic<\/strong> species is one which is naturally found only in a specific geographic area that is usually restricted in size. Other species are generalists: species which live in a wide variety of geographic areas; the raccoon, for example, is native to most of North and Central America.<\/p>\n<p>Species distribution patterns are based on biotic and abiotic factors and their influences during the very long periods of time required for species evolution; therefore, early studies of biogeography were closely linked to the emergence of evolutionary thinking in the eighteenth century. Some of the most distinctive assemblages of plants and animals occur in regions that have been physically separated for millions of years by geographic barriers. Biologists estimate that Australia, for example, has between 600,000 and 700,000 species of plants and animals. Approximately 3\/4 of living plant and mammal species are endemic species found solely in Australia (Figure\u00a01).<\/p>\n<div id=\"attachment_3223\" style=\"width: 1034px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-3223\" class=\"size-large wp-image-3223\" src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/1223\/2017\/02\/10224509\/Figure_44_02_01ab-1024x558.jpg\" alt=\"Photo (a) depicts a wallaby, a member of the kangaroo family. The wallaby is brown with white flecks on its fur and a light brown underbelly. Its hands are clasped together. Photo (b) shows an echidna. Like a porcupine, the echidna has a compact body covered with brown and white quills. It has a long, slender snout.\" width=\"1024\" height=\"558\" \/><\/p>\n<p id=\"caption-attachment-3223\" class=\"wp-caption-text\">Figure 1. Australia is home to many endemic species. The (a) wallaby (Wallabia bicolor), a medium-sized member of the kangaroo family, is a pouched mammal, or marsupial. The (b) echidna (Tachyglossus aculeatus) is an egg-laying mammal. (credit a: modification of work by Derrick Coetzee; credit b: modification of work by Allan Whittome)<\/p>\n<\/div>\n<p>Sometimes ecologists discover unique patterns of species distribution by determining where species are <em>not<\/em> found. Hawaii, for example, has no native land species of reptiles or amphibians, and has only one native terrestrial mammal, the hoary bat. Most of New Guinea, as another example, lacks placental mammals.<\/p>\n<div class=\"textbox\">\n<p>Check out this video to observe a platypus swimming in its natural habitat in New South Wales, Australia. Note that this video has no narration.<\/p>\n<div style=\"width: 640px;\" class=\"wp-video\"><!--[if lt IE 9]><script>document.createElement('video');<\/script><![endif]--><br \/>\n<video class=\"wp-video-shortcode\" id=\"video-3206-1\" width=\"640\" height=\"480\" preload=\"metadata\" controls=\"controls\"><source type=\"video\/mp4\" src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/1223\/2017\/04\/13160921\/6822054037_sd.mp4?_=1\" \/><a href=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/1223\/2017\/04\/13160921\/6822054037_sd.mp4\">https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/1223\/2017\/04\/13160921\/6822054037_sd.mp4<\/a><\/video><\/div>\n<\/div>\n<p>Like animals, plants can be endemic or generalists: endemic plants are found only on specific regions of the Earth, while generalists are found on many regions. Isolated land masses\u2014such as Australia, Hawaii, and Madagascar\u2014often have large numbers of endemic plant species. Some of these plants are endangered due to human activity. The forest gardenia (<em>Gardenia brighamii<\/em>), for instance, is endemic to Hawaii; only an estimated 15\u201320 trees are thought to exist (Figure 2).<\/p>\n<div style=\"width: 361px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" id=\"5\" class=\"\" src=\"https:\/\/openstax.org\/resources\/c09285b9cd10fd5ac4a92b823f9559a7319461a2\" alt=\"The photo shows a white flower with seven smooth, diamond-shaped petals radiating out from a yellow center. The flower is surrounded by waxy green leaves.\" width=\"351\" height=\"315\" data-media-type=\"image\/jpg\" \/><\/p>\n<p class=\"wp-caption-text\">Figure 2. Listed as federally endangered, the forest gardenia is a small tree with distinctive flowers. It is found only in five of the Hawaiian Islands in small populations consisting of a few individual specimens. (credit: Forest &amp; Kim Starr)<\/p>\n<\/div>\n<p>&nbsp;<\/p>\n<div class=\"textbox tryit\">\n<h3>Try It<\/h3>\n<p>\t<iframe id=\"assessment_practice_5d4f0972-5c8e-4058-9e3b-913abe2e8a23\" class=\"resizable\" src=\"https:\/\/assess.lumenlearning.com\/practice\/5d4f0972-5c8e-4058-9e3b-913abe2e8a23?iframe_resize_id=assessment_practice_id_5d4f0972-5c8e-4058-9e3b-913abe2e8a23\" frameborder=\"0\" style=\"border:none;width:100%;height:100%;min-height:300px;\"><br \/>\n\t<\/iframe><br \/>\n\t<iframe id=\"assessment_practice_623076b4-2195-4b95-b5c1-e30af5922508\" class=\"resizable\" src=\"https:\/\/assess.lumenlearning.com\/practice\/623076b4-2195-4b95-b5c1-e30af5922508?iframe_resize_id=assessment_practice_id_623076b4-2195-4b95-b5c1-e30af5922508\" frameborder=\"0\" style=\"border:none;width:100%;height:100%;min-height:300px;\"><br \/>\n\t<\/iframe>\n<\/div>\n\n\t\t\t <section class=\"citations-section\" role=\"contentinfo\">\n\t\t\t <h3>Candela Citations<\/h3>\n\t\t\t\t\t <div>\n\t\t\t\t\t\t <div id=\"citation-list-3206\">\n\t\t\t\t\t\t\t <div class=\"licensing\"><div class=\"license-attribution-dropdown-subheading\">CC licensed content, Shared previously<\/div><ul class=\"citation-list\"><li>Biology 2e. <strong>Provided by<\/strong>: OpenStax. <strong>Located at<\/strong>: <a target=\"_blank\" href=\"http:\/\/cnx.org\/contents\/185cbf87-c72e-48f5-b51e-f14f21b5eabd@10.8\">http:\/\/cnx.org\/contents\/185cbf87-c72e-48f5-b51e-f14f21b5eabd@10.8<\/a>. <strong>License<\/strong>: <em><a target=\"_blank\" rel=\"license\" href=\"https:\/\/creativecommons.org\/licenses\/by\/4.0\/\">CC BY: Attribution<\/a><\/em>. <strong>License Terms<\/strong>: Access for free at https:\/\/openstax.org\/books\/biology-2e\/pages\/1-introduction<\/li><li>Platypus Movie. <strong>Authored by<\/strong>: Alan Couch. <strong>Located at<\/strong>: <a target=\"_blank\" href=\"https:\/\/flic.kr\/p\/boQNZk\">https:\/\/flic.kr\/p\/boQNZk<\/a>. <strong>License<\/strong>: <em><a target=\"_blank\" rel=\"license\" href=\"https:\/\/creativecommons.org\/licenses\/by\/4.0\/\">CC BY: Attribution<\/a><\/em><\/li><\/ul><\/div>\n\t\t\t\t\t\t <\/div>\n\t\t\t\t\t <\/div>\n\t\t\t <\/section>","protected":false},"author":17,"menu_order":7,"template":"","meta":{"_candela_citation":"[{\"type\":\"cc\",\"description\":\"Biology 2e\",\"author\":\"\",\"organization\":\"OpenStax\",\"url\":\"http:\/\/cnx.org\/contents\/185cbf87-c72e-48f5-b51e-f14f21b5eabd@10.8\",\"project\":\"\",\"license\":\"cc-by\",\"license_terms\":\"Access for free at https:\/\/openstax.org\/books\/biology-2e\/pages\/1-introduction\"},{\"type\":\"cc\",\"description\":\"Platypus Movie\",\"author\":\"Alan Couch\",\"organization\":\"\",\"url\":\"https:\/\/flic.kr\/p\/boQNZk\",\"project\":\"\",\"license\":\"cc-by\",\"license_terms\":\"\"}]","CANDELA_OUTCOMES_GUID":"59cee303-50a5-486c-8233-762f32bc1703, 890bdf7c-d756-47b4-ae91-b73319a574d8, dcda7bb4-475f-4d51-8a2f-e55f6ea6f278","pb_show_title":"on","pb_short_title":"","pb_subtitle":"","pb_authors":[],"pb_section_license":""},"chapter-type":[],"contributor":[],"license":[],"class_list":["post-3206","chapter","type-chapter","status-publish","hentry"],"part":3091,"_links":{"self":[{"href":"https:\/\/courses.lumenlearning.com\/wm-biology2\/wp-json\/pressbooks\/v2\/chapters\/3206","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/courses.lumenlearning.com\/wm-biology2\/wp-json\/pressbooks\/v2\/chapters"}],"about":[{"href":"https:\/\/courses.lumenlearning.com\/wm-biology2\/wp-json\/wp\/v2\/types\/chapter"}],"author":[{"embeddable":true,"href":"https:\/\/courses.lumenlearning.com\/wm-biology2\/wp-json\/wp\/v2\/users\/17"}],"version-history":[{"count":14,"href":"https:\/\/courses.lumenlearning.com\/wm-biology2\/wp-json\/pressbooks\/v2\/chapters\/3206\/revisions"}],"predecessor-version":[{"id":8744,"href":"https:\/\/courses.lumenlearning.com\/wm-biology2\/wp-json\/pressbooks\/v2\/chapters\/3206\/revisions\/8744"}],"part":[{"href":"https:\/\/courses.lumenlearning.com\/wm-biology2\/wp-json\/pressbooks\/v2\/parts\/3091"}],"metadata":[{"href":"https:\/\/courses.lumenlearning.com\/wm-biology2\/wp-json\/pressbooks\/v2\/chapters\/3206\/metadata\/"}],"wp:attachment":[{"href":"https:\/\/courses.lumenlearning.com\/wm-biology2\/wp-json\/wp\/v2\/media?parent=3206"}],"wp:term":[{"taxonomy":"chapter-type","embeddable":true,"href":"https:\/\/courses.lumenlearning.com\/wm-biology2\/wp-json\/pressbooks\/v2\/chapter-type?post=3206"},{"taxonomy":"contributor","embeddable":true,"href":"https:\/\/courses.lumenlearning.com\/wm-biology2\/wp-json\/wp\/v2\/contributor?post=3206"},{"taxonomy":"license","embeddable":true,"href":"https:\/\/courses.lumenlearning.com\/wm-biology2\/wp-json\/wp\/v2\/license?post=3206"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}