<story><title>Our closest worm kin regrow body parts, raising hopes of regeneration in humans</title><url>http://www.washington.edu/news/2016/11/28/our-closest-worm-kin-regrow-body-parts-raising-hopes-of-regeneration-in-humans/</url></story><parent_chain><item><author>xux</author><text>A lot of people are focusing on the mechanics, but it seems like humans don&amp;#x27;t generate body parts just like cells don&amp;#x27;t generate organelles. The entity is not _meant_ to exist by itself, but form a cohesive living group.&lt;p&gt;A cell doesn&amp;#x27;t need to repair itself, it can simply clone itself and then die. A human being doesn&amp;#x27;t need to regenerate itself because it can reproduce and be cleared away. Evolution evolved to ensure the survival of the species, not the individual.&lt;p&gt;The human being is constantly generating itself by multiplying cells. Similarly, the species is constantly generating itself by multiplying individuals.</text></item></parent_chain><comment><author>richardw</author><text>Those mechanisms are good enough to have brought us to this point, but that has no bearing on what kind of future we choose to create for ourselves.&lt;p&gt;Metals rust and seep into the ground, but we dig them up and build spacecraft from them. Metals aren&amp;#x27;t _meant_ to do that, but we have some influence over our environment. We might end up having a similar influence over our cells.</text></comment>
<story><title>Our closest worm kin regrow body parts, raising hopes of regeneration in humans</title><url>http://www.washington.edu/news/2016/11/28/our-closest-worm-kin-regrow-body-parts-raising-hopes-of-regeneration-in-humans/</url></story><parent_chain><item><author>xux</author><text>A lot of people are focusing on the mechanics, but it seems like humans don&amp;#x27;t generate body parts just like cells don&amp;#x27;t generate organelles. The entity is not _meant_ to exist by itself, but form a cohesive living group.&lt;p&gt;A cell doesn&amp;#x27;t need to repair itself, it can simply clone itself and then die. A human being doesn&amp;#x27;t need to regenerate itself because it can reproduce and be cleared away. Evolution evolved to ensure the survival of the species, not the individual.&lt;p&gt;The human being is constantly generating itself by multiplying cells. Similarly, the species is constantly generating itself by multiplying individuals.</text></item></parent_chain><comment><author>devoply</author><text>&amp;gt; Evolution evolved to ensure the survival of the species, not the individual.&lt;p&gt;At some point in our evolutionary history the cells in our body made this choice. Evolution favors survival and potentially reproduction, because otherwise you are no longer in the game. So there was some evolutionary constraint that caused those genes not to regenerate parts.&lt;p&gt;It&amp;#x27;s possible we can change things so that those genes are active again. But we don&amp;#x27;t really understand these systems well enough to do that and won&amp;#x27;t anytime soon. But science carries on and I am sure you can make lab mice to test hypotheses of how this might work in mammals. And we probably will very soon, if not here then in China.&lt;p&gt;Evolution is perfectly fine even if you don&amp;#x27;t reproduce much, as long as you continue to survive in your environment. There are creatures out there that have changed very little and we  know this because we have fossil records, and this is because they have been adapted to their environment and stayed adapted despite the environmental changes. And there are even immortal creature that die not because their bodies age and kill them but because they are eaten by other things, but still they don&amp;#x27;t change much over time. I guess you could say they are better evolved than other creatures that have to constantly change. They made better evolutionary decisions than other creatures very early on.</text></comment>