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Weeds and Invasive species

Me and a friend of mine (an ecologist in training) were talking about weeds (plants) and i asked her about the advantages they have over natives that lets them thrive. She mentioned the fact that they might be alien species, transported to a new location devoid of their natural predators, therefore giving them the advantage to grow faster than the native species. There might also be other genetic variations which help the weeds. And given that weeds, by definition, can pop up at most places on earth and are hardly affected by drought/disease, scientists are trying to understand the genetic mutations they have that give raise to such abilities. By understanding the science behind the resilience of weeds, one can make agricultural crops less prone to drought/disease.

This got me thinking about invasive species in general. Not just plants but a good number of animal species were introduced to new parts of the world, some intentionally and some accidentally. Here's a non-exhaustive list of introduced (invasive) species (wiki) and here are a few interesting accounts of how certain invasive species were introduced (wiki). It'd be really interesting to read a more detailed account of the story of such species and the repercussions they've had on the native flora and fauna.

PS : I always wondered about the diversity of dogs, in terms of shape and size, and how they all belong to the same species. I read about how certain breeds of dogs were bred to do certain things. For example, in 19th century London, there was a breed of dog whose daily routine it was to run in a wheel, which through a contraption, spins food over a grill. The history of animal species is a fascinating subject, one that I hope to dig deeper into in the near future ...

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