The most common type of hyperthyroidism disease is an autoimmune subtype called Hashimoto's thyroiditis.
Answer:
when farmers select animals or plants to use for breeding they look for <em>natural</em><em> </em><em>variat</em><em>ions</em><em> </em><em>pres</em><em>ent</em><em> </em><em>in</em><em> </em><em>a</em><em> </em><em>species</em><em>.</em>
<em>hop</em><em>e</em><em> it</em><em> helps</em><em>!</em>
It would cause competition
they will strive to get the resources they need but because there are so many some may not get enough nutrients