As in the case of swine-origin influenza A/H1N1, which is
26 caused by mutation of influenza H1N1 and has rapidly
27 spread to every continent in 2009, the emergence of new
28 organisms due to mutation can cause disturbance of exist-
29 ing ecosystems. On the other hand, even if sickle cell ane-
30 mia acts as a harmful mutation in most environments, it
31 can act as a beneficial mutant by virtue of the heterozy-
32 gote advantage and may promote human survival in
33 malaria-infested regions. Like these examples, mutation
34 has both positive and negative effects.
35 Existing ecosystems may be also disturbed by the
36 influx of new alien species. For example, Neutria
37 (Myocastor coypus) and Bull frog (Rana catesbeiana)
38 quickly destroy
26 caused by mutation of influenza H1N1 and has rapidly
27 spread to every continent in 2009, the emergence of new
28 organisms due to mutation can cause disturbance of exist-
29 ing ecosystems. On the other hand, even if sickle cell ane-
30 mia acts as a harmful mutation in most environments, it
31 can act as a beneficial mutant by virtue of the heterozy-
32 gote advantage and may promote human survival in
33 malaria-infested regions. Like these examples, mutation
34 has both positive and negative effects.
35 Existing ecosystems may be also disturbed by the
36 influx of new alien species. For example, Neutria
37 (Myocastor coypus) and Bull frog (Rana catesbeiana)
38 quickly destroy