What form of reproduction did the first animals on land use*? Were they hermaphrodites, or did they have male and female sexes? [Is there a proper term for sexual separation in a species?]

Were any land species believed to have evolved from hermaphrodite ocean species (that crossed to land on roughly the same geological time periods that land creatures first evolved)?

*I know that 'first on land' is a complicated concept itself, since it could mean first creatures be able to survive on land at all, first to freely travel between land and water, or first to only live on land, or anywhere in between. I assume all three categories were sexual though?

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    $\begingroup$ Are you thinking of vertebrates or non-vertebrates? $\endgroup$
    – kmm
    Jul 23, 2015 at 21:26
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    $\begingroup$ Your questions are quite wordy. Please be to the point. Condense the question by cutting the fluff, reducing details and exclude irrelevant random thoughts. $\endgroup$
    – AliceD
    Jul 23, 2015 at 23:52
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    $\begingroup$ I think the term you are looking for is sexual dimorphism. Or just sexual reproduction. $\endgroup$
    – MattDMo
    Jul 24, 2015 at 13:42


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