{"id":200,"date":"2014-08-14T19:04:07","date_gmt":"2014-08-14T19:04:07","guid":{"rendered":"http:\/\/www.naturewatch.ca\/wormwatch\/?page_id=200"},"modified":"2014-11-13T20:20:01","modified_gmt":"2014-11-13T20:20:01","slug":"anatomy","status":"publish","type":"page","link":"https:\/\/www.naturewatch.ca\/wormwatch\/how-to-guide\/anatomy\/","title":{"rendered":"anatomy"},"content":{"rendered":"<p><a href=\"\/wormwatch\/wp-content\/uploads\/sites\/5\/2014\/08\/Fotolia_12405880_Subscription_XL.jpg\"><img decoding=\"async\" class=\"alignnone size-full wp-image-201\" src=\"\/wormwatch\/wp-content\/uploads\/sites\/5\/2014\/08\/Fotolia_12405880_Subscription_XL.jpg\" alt=\"Fotolia_12405880_Subscription_XL\" width=\"100%\" srcset=\"https:\/\/www.naturewatch.ca\/wormwatch\/wp-content\/uploads\/sites\/5\/2014\/08\/Fotolia_12405880_Subscription_XL.jpg 1000w, https:\/\/www.naturewatch.ca\/wormwatch\/wp-content\/uploads\/sites\/5\/2014\/08\/Fotolia_12405880_Subscription_XL-300x168.jpg 300w\" sizes=\"(max-width: 1000px) 100vw, 1000px\" \/><\/a><\/p>\n<p>The following table outlines the anatomical characteristics of earthworms:<\/p>\n<div style=\"border: solid 1px #ccc; width: 100%;\">\n<div style=\"float: left; width: 98%; border-bottom: solid #ccc 1px; padding: 1% 0;\">\n<div style=\"font-weight: bold; width: 40%; float: left; text-align: left; padding-left: 5px;\">Characteristic<\/div>\n<div style=\"width: 50%; float: left; text-align: left; font-weight: bold; padding-left: 25px;\">Definition<\/div>\n<\/div>\n<div style=\"float: left; width: 98%; border-bottom: solid #ccc 1px; padding: 1% 0; background-color: #fde7ce;\">\n<div style=\"color: #a2662b; font-weight: bold; width: 40%; float: left; padding-left: 1%;\">Invertebrate<\/div>\n<div style=\"width: 57%; float: left;\">\n<ul type=\"disc\">\n<li>No back bone<\/li>\n<\/ul>\n<\/div>\n<\/div>\n<div style=\"float: left; width: 98%; border-bottom: solid #ccc 1px; padding: 1% 0;\">\n<div style=\"color: #a2662b; font-weight: bold; width: 40%; float: left; padding-left: 1%;\">Annelid<\/div>\n<div style=\"width: 57%; float: left;\">\n<ul type=\"disc\">\n<li>Body is segmented<\/li>\n<\/ul>\n<\/div>\n<\/div>\n<div style=\"float: left; width: 98%; border-bottom: solid #ccc 1px; padding: 1% 0; background-color: #fde7ce;\">\n<div style=\"color: #a2662b; font-weight: bold; width: 40%; float: left; padding-left: 1%;\">Bilateral Symmetry<\/div>\n<div style=\"width: 57%; float: left;\">\n<ul type=\"disc\">\n<li>If you cut an earthworm down the centre, you would find that the left and the right sides of its body are identical or symmetrical<\/li>\n<\/ul>\n<\/div>\n<\/div>\n<div style=\"float: left; width: 98%; border-bottom: solid #ccc 1px; padding: 1% 0;\">\n<div style=\"color: #a2662b; font-weight: bold; width: 40%; float: left; padding-left: 1%;\">Member of the class Oligochaeta<\/div>\n<div style=\"width: 57%; float: left;\">\n<ul type=\"disc\">\n<li>They crawl using circular and longitudinal muscles which are located under the epidermis<\/li>\n<li>Each segment also has bristle like setae (<a href=\"#Figure1\">see figure 1<\/a>) which help to anchor their segments as they crawl<\/li>\n<\/ul>\n<\/div>\n<\/div>\n<div style=\"float: left; width: 98%; border-bottom: solid #ccc 1px; padding: 1% 0; background-color: #fde7ce;\">\n<div style=\"color: #a2662b; font-weight: bold; width: 40%; float: left; padding-left: 1%;\">Basic Respiratory System<\/div>\n<div style=\"width: 57%; float: left;\">\n<ul type=\"disc\">\n<li>Unlike humans, earthworms do not have a well-developed respiratory system<\/li>\n<li>Instead of lungs, they breathe through their skin which needs to stay moist for breathing<\/li>\n<\/ul>\n<\/div>\n<\/div>\n<div style=\"float: left; width: 98%; border-bottom: solid #ccc 1px; padding: 1% 0;\">\n<div style=\"color: #a2662b; font-weight: bold; width: 40%; float: left; padding-left: 1%;\">Closed Circulatory System<\/div>\n<div style=\"width: 57%; float: left;\">\n<ul type=\"disc\">\n<li>Unlike many other invertebrates, the circulatory system is fully closed<\/li>\n<li>One large blood vessel runs the length of the body, immediately beside the gut<\/li>\n<li>Two to five pairs of muscular blood vessels extend from the central vessel and function as hearts to drive the circulatory system<\/li>\n<\/ul>\n<\/div>\n<\/div>\n<\/div>\n<p><strong>The following image illustrates earthworm anatomy:<\/strong><\/p>\n<p><a id=\"Figure1\" name=\"Figure1\"><\/a><a href=\"\/wormwatch\/wp-content\/uploads\/sites\/5\/2014\/08\/anatom_en.jpg\" target=\"_blank\"><img decoding=\"async\" class=\"alignnone wp-image-205 size-full\" title=\"Figure 1\" src=\"\/wormwatch\/wp-content\/uploads\/sites\/5\/2014\/08\/anatom_en.jpg\" alt=\"Figure 1\" width=\"100%\" srcset=\"https:\/\/www.naturewatch.ca\/wormwatch\/wp-content\/uploads\/sites\/5\/2014\/08\/anatom_en.jpg 746w, https:\/\/www.naturewatch.ca\/wormwatch\/wp-content\/uploads\/sites\/5\/2014\/08\/anatom_en-300x131.jpg 300w\" sizes=\"(max-width: 746px) 100vw, 746px\" \/><\/a><br \/>\n<span style=\"text-align: center; font-style: italic; font-weight: bold;\">Figure 1: Anatomy of an earthworm<\/span><\/p>\n<p>The first segment of the earthworm, the <a title=\"The first segment of the earthworm\u00eds body; contains the mouth.\" href=\"#\" rel=\"tooltip\">peristomium<\/a> (<a href=\"#Figure1\">see figure 1<\/a>), contains the mouth. There is a small tongue-like lobe just above the mouth called the <a title=\"The lobe of skin that projects out in front of the first body segment (peristomium). It is located above the mouth, and there are three formations as seen in dorsal view.\" href=\"#\" rel=\"tooltip\">prostomium<\/a> (<a href=\"#Figure1\">see figure 1<\/a>). Earthworms use the prostomium to see their environment, as earthworms have no eyes, ears, nose or hands. They depend on the prostomium and skin to help it feel their way through the soil.<\/p>\n<p>As the earthworm tunnels through the soil, it excretes mucus from its body. This mucus reacts with the soil of the tunnel walls and forms a type of cement which makes the tunnel walls stable so that the tunnel can be reused.<\/p>\n<p>The earthworm brain is actually a fused pair of nerve ganglia, mostly located in the third segment. There are three giant nerve fibres that run the length of the body, around the gut. These fibres transmit impulses from the brain which control rapid body movements.<\/p>\n<p>About one third of the way down the earthworm (from the head) is the <a title=\"A swelling in the skin near the head that secretes material to form cocoons. The clitellum forms a band that can be flared, non-flared, saddle shaped, or annular. The clitellum is generally found between segments 26-33.\" href=\"#\" rel=\"tooltip\">clitellum<\/a> (<a href=\"#Figure1\">see figure 1<\/a>). The clitellum is a swelling of the skin and can only be seen in earthworms that are ready to reproduce. It may be white, orange-red or reddish-brown in colour. Earthworms are ready to mate when their clitellum is orange. Most of the material secreted to form earthworm cocoons is produced within the clitellum. The number of the segments to where the clitellum begins and the number of segments that make up the clitellum are important for identifying earthworms.<\/p>\n<p>The very last segment is called the <a title=\"The last segment of the earthworm\u00eds body; contains the anus.\" href=\"#\" rel=\"tooltip\">periproct<\/a> (<a href=\"#Figure1\">see figure 1<\/a>) and contains the anus.<\/p>\n<p>Except for the first and last segment, all the other segments have eight <a title=\"The bristles (or hairs) that are found on an earthworm\u00eds body. They help the earthworm to move and act to sense the environment.\" href=\"#\" rel=\"tooltip\">setae<\/a> located around each segment. The setae look like small bristles sticking out of the earthworm\u2019s skin. The setae can be retracted and are for moving through the soil. The bristle-like setae anchor the segments as they crawl.<\/p>\n<h4><strong>How to identify different earthworms:<\/strong><\/h4>\n<p>The number of segments from the peristomium to the clitellum and the number of segments which make up the clitellum are species specific in earthworms. This means that if two earthworms have different numbers of segments leading up to the start of the clitellum, they are different earthworm species.<\/p>\n<p>In Canada, there are three families of earthworms represented:<\/p>\n<ul>\n<li><em>Lumbricidae <\/em><\/li>\n<li><em>Acanthodrilidae<\/em><\/li>\n<li><em>Sparganophilidae<\/em><\/li>\n<\/ul>\n<p>There are some species of earthworms that are native to North America and Canada:<\/p>\n<ul>\n<li><em>Aporrectodea bowcrowensis<\/em><\/li>\n<li><em>Bimastos lawrenceae<\/em><\/li>\n<li><em>Arctiostrotus perrieri<\/em><\/li>\n<li><em>Arctiostrotus vancouverensis <\/em><\/li>\n<li><em>Toutellus oregonensis<\/em><\/li>\n<li><em>Sparganophilus eiseni<\/em><\/li>\n<\/ul>\n<p>Currently, 25 different earthworm species have been found and identified in Canada. Perhaps with your help we can find more!<\/p>\n<h4><strong>How to tell juveniles from adults.<\/strong><\/h4>\n<p>Those earthworms without genital markings such as the clitellum, <a title=\"Glandular swellings that occur on both sides of the clitellum. They are not always present, and they can be continuous or discontinuous with the clitellum. Their size and shape may vary from long narrow bands, triangles, or sucker-like shapes, depending on the species.\" href=\"#\" rel=\"tooltip\">tubercula pubertatis<\/a> (<a href=\"#Figure1\">see figure 1<\/a>), or <a title=\"Areas of modified epidermis without distinct boundaries, through which follicles of genital setae open.\" href=\"#\" rel=\"tooltip\">genital tumescence<\/a> are juveniles. This stage of the life cycle is located between the hatchling phase and the appearance of genital markings (adult stage).<\/p>\n<div style=\"float: left; width: 100%;\"><a name=\"figure2\"><\/a><br \/>\n<a href=\"\/wormwatch\/wp-content\/uploads\/sites\/5\/2014\/08\/cocon_Eartworm_en1.jpg\"><img loading=\"lazy\" decoding=\"async\" width=\"360\" height=\"266\" class=\"alignnone wp-image-213 size-full\" src=\"\/wormwatch\/wp-content\/uploads\/sites\/5\/2014\/08\/cocon_Eartworm_en1.jpg\" alt=\"\" align=\"left\" srcset=\"https:\/\/www.naturewatch.ca\/wormwatch\/wp-content\/uploads\/sites\/5\/2014\/08\/cocon_Eartworm_en1.jpg 360w, https:\/\/www.naturewatch.ca\/wormwatch\/wp-content\/uploads\/sites\/5\/2014\/08\/cocon_Eartworm_en1-300x221.jpg 300w\" sizes=\"auto, (max-width: 360px) 100vw, 360px\" \/><\/a><br \/>\n<span style=\"text-align: left; font-style: italic; font-weight: bold;\">Figure 2: Earthworm cocoon.<\/span><\/div>\n<div style=\"float: left; width: 100%;\">\n<p>Other stages in the life of an earthworm:<\/p>\n<ol>\n<li>Earthworms reproduce by laying a <a title=\"A sac that contains the earthworm\u00eds eggs. The cocoon is formed at the clitellum, and then travels from the clitellum to the head. Here it slides off the earthworm\u00eds body and is deposited into the soil.\" href=\"#\" rel=\"tooltip\">cocoon<\/a> \u2013 a sac that contains the earthworm\u2019s eggs<\/li>\n<li>The cocoon is formed at the clitellum, and then travels from the clitellum to the head<\/li>\n<li>Once it reaches the head, the cocoon slides off the earthworm\u2019s body and is deposited into the soil<\/li>\n<\/ol>\n<\/div>\n<div style=\"float: left; width: 100%;\"><a href=\"\/wormwatch\/wp-content\/uploads\/sites\/5\/2014\/08\/cocon_Aestivating_en.jpg\"><img loading=\"lazy\" decoding=\"async\" width=\"360\" height=\"296\" class=\"alignnone size-full wp-image-210\" src=\"\/wormwatch\/wp-content\/uploads\/sites\/5\/2014\/08\/cocon_Aestivating_en.jpg\" alt=\"cocon_Aestivating_en\" align=\"left\" srcset=\"https:\/\/www.naturewatch.ca\/wormwatch\/wp-content\/uploads\/sites\/5\/2014\/08\/cocon_Aestivating_en.jpg 360w, https:\/\/www.naturewatch.ca\/wormwatch\/wp-content\/uploads\/sites\/5\/2014\/08\/cocon_Aestivating_en-300x246.jpg 300w\" sizes=\"auto, (max-width: 360px) 100vw, 360px\" \/><\/a><br \/>\n<span style=\"text-align: left; font-style: italic; font-weight: bold;\">Figure 3: Aestivating earthworm.<\/span><\/div>\n<p style=\"float: left; width: 100%;\">Earthworms can enter into periods of inactivity or dormancy as a result of unfavourable conditions (e.g. dry periods). This is known as aestivation. During aestivation, the earthworm curls up into a knot and becomes quite pink.<\/p>\n<p><script src=\"js\/main.js\"><\/script><br \/>\n<script src=\"js\/tooltip.js\"><\/script><\/p>\n","protected":false},"excerpt":{"rendered":"<p>The following table outlines the anatomical characteristics of earthworms: Characteristic Definition Invertebrate No back bone Annelid Body is segmented Bilateral Symmetry If you cut an earthworm down the centre, you would find that the left and the right sides of&hellip; <\/p>\n","protected":false},"author":2,"featured_media":0,"parent":28,"menu_order":2,"comment_status":"closed","ping_status":"open","template":"","meta":{"footnotes":""},"class_list":["post-200","page","type-page","status-publish","hentry"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v23.4 - https:\/\/yoast.com\/wordpress\/plugins\/seo\/ -->\n<title>anatomy - WormWatch<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/www.naturewatch.ca\/wormwatch\/how-to-guide\/anatomy\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"anatomy - WormWatch\" \/>\n<meta property=\"og:description\" content=\"The following table outlines the anatomical characteristics of earthworms: Characteristic Definition Invertebrate No back bone Annelid Body is segmented Bilateral Symmetry If you cut an earthworm down the centre, you would find that the left and the right sides of&hellip;\" \/>\n<meta property=\"og:url\" content=\"https:\/\/www.naturewatch.ca\/wormwatch\/how-to-guide\/anatomy\/\" \/>\n<meta property=\"og:site_name\" content=\"WormWatch\" \/>\n<meta property=\"article:publisher\" content=\"https:\/\/www.facebook.com\/NatureWatchAttentionNature\" \/>\n<meta property=\"article:modified_time\" content=\"2014-11-13T20:20:01+00:00\" \/>\n<meta property=\"og:image\" content=\"https:\/\/www.naturewatch.ca\/wormwatch\/wp-content\/uploads\/sites\/5\/2014\/08\/Fotolia_12405880_Subscription_XL.jpg\" \/>\n<meta name=\"twitter:label1\" content=\"Est. reading time\" \/>\n\t<meta name=\"twitter:data1\" content=\"4 minutes\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\/\/schema.org\",\"@graph\":[{\"@type\":\"WebPage\",\"@id\":\"https:\/\/www.naturewatch.ca\/wormwatch\/how-to-guide\/anatomy\/\",\"url\":\"https:\/\/www.naturewatch.ca\/wormwatch\/how-to-guide\/anatomy\/\",\"name\":\"anatomy - WormWatch\",\"isPartOf\":{\"@id\":\"https:\/\/www.naturewatch.ca\/wormwatch\/#website\"},\"datePublished\":\"2014-08-14T19:04:07+00:00\",\"dateModified\":\"2014-11-13T20:20:01+00:00\",\"breadcrumb\":{\"@id\":\"https:\/\/www.naturewatch.ca\/wormwatch\/how-to-guide\/anatomy\/#breadcrumb\"},\"inLanguage\":\"en-US\",\"potentialAction\":[{\"@type\":\"ReadAction\",\"target\":[\"https:\/\/www.naturewatch.ca\/wormwatch\/how-to-guide\/anatomy\/\"]}]},{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\/\/www.naturewatch.ca\/wormwatch\/how-to-guide\/anatomy\/#breadcrumb\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"Home\",\"item\":\"https:\/\/www.naturewatch.ca\/wormwatch\/\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"how to guide\",\"item\":\"https:\/\/www.naturewatch.ca\/wormwatch\/how-to-guide\/\"},{\"@type\":\"ListItem\",\"position\":3,\"name\":\"anatomy\"}]},{\"@type\":\"WebSite\",\"@id\":\"https:\/\/www.naturewatch.ca\/wormwatch\/#website\",\"url\":\"https:\/\/www.naturewatch.ca\/wormwatch\/\",\"name\":\"WormWatch\",\"description\":\"Engaging Citizens in Science\",\"potentialAction\":[{\"@type\":\"SearchAction\",\"target\":{\"@type\":\"EntryPoint\",\"urlTemplate\":\"https:\/\/www.naturewatch.ca\/wormwatch\/?s={search_term_string}\"},\"query-input\":{\"@type\":\"PropertyValueSpecification\",\"valueRequired\":true,\"valueName\":\"search_term_string\"}}],\"inLanguage\":\"en-US\"}]}<\/script>\n<!-- \/ Yoast SEO plugin. -->","yoast_head_json":{"title":"anatomy - WormWatch","robots":{"index":"index","follow":"follow","max-snippet":"max-snippet:-1","max-image-preview":"max-image-preview:large","max-video-preview":"max-video-preview:-1"},"canonical":"https:\/\/www.naturewatch.ca\/wormwatch\/how-to-guide\/anatomy\/","og_locale":"en_US","og_type":"article","og_title":"anatomy - WormWatch","og_description":"The following table outlines the anatomical characteristics of earthworms: Characteristic Definition Invertebrate No back bone Annelid Body is segmented Bilateral Symmetry If you cut an earthworm down the centre, you would find that the left and the right sides of&hellip;","og_url":"https:\/\/www.naturewatch.ca\/wormwatch\/how-to-guide\/anatomy\/","og_site_name":"WormWatch","article_publisher":"https:\/\/www.facebook.com\/NatureWatchAttentionNature","article_modified_time":"2014-11-13T20:20:01+00:00","og_image":[{"url":"https:\/\/www.naturewatch.ca\/wormwatch\/wp-content\/uploads\/sites\/5\/2014\/08\/Fotolia_12405880_Subscription_XL.jpg"}],"twitter_misc":{"Est. reading time":"4 minutes"},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"WebPage","@id":"https:\/\/www.naturewatch.ca\/wormwatch\/how-to-guide\/anatomy\/","url":"https:\/\/www.naturewatch.ca\/wormwatch\/how-to-guide\/anatomy\/","name":"anatomy - WormWatch","isPartOf":{"@id":"https:\/\/www.naturewatch.ca\/wormwatch\/#website"},"datePublished":"2014-08-14T19:04:07+00:00","dateModified":"2014-11-13T20:20:01+00:00","breadcrumb":{"@id":"https:\/\/www.naturewatch.ca\/wormwatch\/how-to-guide\/anatomy\/#breadcrumb"},"inLanguage":"en-US","potentialAction":[{"@type":"ReadAction","target":["https:\/\/www.naturewatch.ca\/wormwatch\/how-to-guide\/anatomy\/"]}]},{"@type":"BreadcrumbList","@id":"https:\/\/www.naturewatch.ca\/wormwatch\/how-to-guide\/anatomy\/#breadcrumb","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https:\/\/www.naturewatch.ca\/wormwatch\/"},{"@type":"ListItem","position":2,"name":"how to guide","item":"https:\/\/www.naturewatch.ca\/wormwatch\/how-to-guide\/"},{"@type":"ListItem","position":3,"name":"anatomy"}]},{"@type":"WebSite","@id":"https:\/\/www.naturewatch.ca\/wormwatch\/#website","url":"https:\/\/www.naturewatch.ca\/wormwatch\/","name":"WormWatch","description":"Engaging Citizens in Science","potentialAction":[{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https:\/\/www.naturewatch.ca\/wormwatch\/?s={search_term_string}"},"query-input":{"@type":"PropertyValueSpecification","valueRequired":true,"valueName":"search_term_string"}}],"inLanguage":"en-US"}]}},"_links":{"self":[{"href":"https:\/\/www.naturewatch.ca\/wormwatch\/wp-json\/wp\/v2\/pages\/200","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.naturewatch.ca\/wormwatch\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/www.naturewatch.ca\/wormwatch\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/www.naturewatch.ca\/wormwatch\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.naturewatch.ca\/wormwatch\/wp-json\/wp\/v2\/comments?post=200"}],"version-history":[{"count":49,"href":"https:\/\/www.naturewatch.ca\/wormwatch\/wp-json\/wp\/v2\/pages\/200\/revisions"}],"predecessor-version":[{"id":798,"href":"https:\/\/www.naturewatch.ca\/wormwatch\/wp-json\/wp\/v2\/pages\/200\/revisions\/798"}],"up":[{"embeddable":true,"href":"https:\/\/www.naturewatch.ca\/wormwatch\/wp-json\/wp\/v2\/pages\/28"}],"wp:attachment":[{"href":"https:\/\/www.naturewatch.ca\/wormwatch\/wp-json\/wp\/v2\/media?parent=200"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}