Are human fetuses parasites?

[tabibito]

A parasite harms it's host.

We have lots of "riders" in us that are not parasites, but symbiots, like the bacteria in our guts, which helps us digest food.

Ah - so a foetus is of the same race as Dax.

[Teallaura]

I say no.

A parasite is defined as an organism of one species living in or on an organism of another species (a heterospecific relationship) and deriving its nourishment from the host (is metabolically dependent on the host). (See Cheng, T.C., General Parasitology, p. 7, 1973.)


Others say yes:

http://www.biology-online.Org/dictionary/Parasite
par·a·site
ˈparəˌsīt/
noun
an organism that lives in or on another organism (its host) and benefits by deriving nutrients at the host's expense.

Actually, now that I think about it, a human embryo would not qualify even under this definition. A parasite rarely announces its presence and the host rarely has a natural mechanism to compensate. A human pregnancy is designed to allow the child to grow while protecting the mother. In pregnancy, a woman naturally compensates for the extra nutritional needs of her child - which is why she puts on a good bit more than the 7 - 10 pounds of baby. A parasite normally causes weight loss as it harms its host; a child stimulates the mother to gain weight instead. A healthy pregnancy is actually good for a woman's overall health - a true parasite is never good for its host.

[Sparko]

A parasite harms it's host.

We have lots of "riders" in us that are not parasites, but symbiots, like the bacteria in our guts, which helps us digest food.

[Bill the Cat]

Not at all. "Fetus" refers to the post-embryonic and pre-birth stage of biological development in viviparous vertebrates. The term "human fetus" therefore refers specifically to a member of the (obviously non-parasitic) species Homo sapiens during this early developmental period.

I think distinguishing between a parasite and parasitic behavior is important to stress in this type of discussion. Something can behave in a parasitic manner, as with kleptoparasitism, while not actually being a parasite.

[CMD]

Not at all. "Fetus" refers to the post-embryonic and pre-birth stage of biological development in viviparous vertebrates. The term "human fetus" therefore refers specifically to a member of the (obviously non-parasitic) species Homo sapiens during this early developmental period.

[Christianbookworm]

The term "parasitic twin" is a misnomer. The proper medical term is "unequal conjoined twin".

I thought it was the old/layman term. Like when a twin has no head and no heart.

[Bill the Cat]

Indeed. You can only call a human a parasite if they're no give all take with no good reason to be. Even then, it isn't a nice thing to call humans. Unless it's a parasitic twin, that isn't even alive...

The term "parasitic twin" is a misnomer. The proper medical term is "unequal conjoined twin".

[Christianbookworm]

How about people that try to make God out to be a genie or vending machine?

[Teallaura]

I think Ivy League Academics are parasites.

[Jedidiah]

I say no.

A parasite is defined as an organism of one species living in or on an organism of another species (a heterospecific relationship) and deriving its nourishment from the host (is metabolically dependent on the host). (See Cheng, T.C., General Parasitology, p. 7, 1973.)


Others say yes:

http://www.biology-online.Org/dictionary/Parasite
par·a·site
ˈparəˌsīt/
noun
an organism that lives in or on another organism (its host) and benefits by deriving nutrients at the host's expense.

The second definition is simply making the assumption that two different species are involved. A fetus is not a parasite. But is a liberal a parasite?

[Christianbookworm]

Indeed. You can only call a human a parasite if they're no give all take with no good reason to be. Even then, it isn't a nice thing to call humans. Unless it's a parasitic twin, that isn't even alive...

[rogue06]

Is a newborn or toddler also a parasite? They can't survive without adult help for long either.

Same with an invalid

[Bill the Cat]

Here is an interesting take on parasitism:

Source: http://en.wikipedia.org/wiki/Kleptoparasitism

Humans

In times of famine intraspecific Kleptoparasitism is common in humans, was even declared legal in Germany until 1975 under the name of Mundraub (Mouth-theft). In Ancient Israel consuming another man's crops was likewise declared legal unless you took something with you in Deuteronomy 23. Humans have been found to chase away lions from their captured prey and consume the meat themselves. A researcher noted the behaviour in Waza National Park, Cameroon in 2006, and other ecologists have suggested that the behaviour may be widespread but often goes unrecognised. Interviews with Bororo herdsmen suggested that they often chase lions away from their prey. This kleptoparasitism may be contributing to the decline of lion populations within the national park

© Copyright Original Source

[Christianbookworm]

Is a newborn or toddler also a parasite? They can't survive without adult help for long either.

[Bill the Cat]

I say no.

A parasite is defined as an organism of one species living in or on an organism of another species (a heterospecific relationship) and deriving its nourishment from the host (is metabolically dependent on the host). (See Cheng, T.C., General Parasitology, p. 7, 1973.)


Others say yes:

http://www.biology-online.Org/dictionary/Parasite
par·a·site
ˈparəˌsīt/
noun
an organism that lives in or on another organism (its host) and benefits by deriving nutrients at the host's expense.