Alvecia wrote:Napkiraly wrote:Inherently detrimental to the host in some capacity, and actually far more constrained according to some textbooks than I even I thought (limiting it between two different species). https://books.google.ca/books?dq=Cheng,+T.C.,+General+Parasitology,+p.+7,+1973&hl=en&id=d4GQlYzode8C&lr=&oi=fnd&ots=l6EmR3PEvV&pg=PP1&sig=wr-51nFxVEYVcWvVnLhfGq8jVls&redir_esc=y#v=onepage&q=Cheng%2C%20T.C.%2C%20General%20Parasitology%2C%20p.%207%2C%201973&f=false Page 2 offers the rough, generalized definition.
The only criteria of note that I can find it violates is that of heterospecific organisms (different species), which:
1) you've already provided an example of a parasite that violates said criteria
2) this book points out these definitions are not universal, but rather "brief", "general", and "often" (not always) used.
Yes, the one outlier whose criteria is actually debatable because of heterospecific preferred definitions but is used as an example as a possibility. Not to mention once again that the relationship is closer to that of mutualism or commensalism between the mother and the fetus. Who would have thunk that there are more than one type of symbiotic or symbiotic like relationships other than parasitism. ¯\_(ツ)_/¯









