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er en af de mest fundamentale enheder i biologien, men p氓 trods af<br />dette, findes der ikke en entydig biologisk definition af begrebet, men<br />derimod adskillige der mere eller mindre anvendes after behov. Det bedst<br />kendte artsbegreb er nok det biologiske artsbegreb, som defineret af Ernst<br />Mayr (1942). Han grupperer individer der sammen kan f氓 fertilt afkom i samme<br />art. Individer fra samme art deler derfor en f忙lles genpulje, og er<br />formeringsm忙ssigt isoleret fra andre arter, dvs. de kan ikke udveksle gener<br />med andre arter. Det mest anvendte artsbegreb er det morfologiske<br />artsbegreb, der grupperer individer der adskiller sig morfologisk fra andre<br />individer i samme art.<br /><br />Af andre mindre anvendte artsbegreber kan n忙vnes det 酶kologiske artsbegreb<br />der kategoriserer individer der deler en bestemt 酶kologisk niche i samme art<br />og det evolution忙re artsbegreb, der kategoriserer individer der <em><a href="fylogeni/index.html" class="internal-link" >fylogenetisk</a></em> har samme stamfader i samme art. Det evolution忙re artsbegreb minder om det<br />biologiske, men inddrager tidsdimensionen og at en art udvikler sig over tid<br />og at nye arter opst氓r ved <a href="artsdannelse/index.html" class="internal-link" ><em>artsdannelse</em></a>. </p> <p><em>Skrevet af <a href="../../../om-evolution/hvem-er-vi/bidragydere/index.html" target="_top" class="internal-link" >Jesper Bechsg氓rd</a></em></p></div></div></div> </div> <div id="content_right"> <div id="fiel_content_right"></div> </div> <div id="footer"> <div id="footerimages"><a target="_blank" href="http://au.dk/" class="au"></a><a target="_blank" href="http://ku.dk/" class="ku"></a></div> <div id="field_footer"><a href="../../../om-evolution/copyright/index.html" >Copyright 漏 evolution.dk og forfatterne.</a> M氓 ikke gengives uden tilladelse. 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