<span>In all eusocial species, sterile workers assist fertile relatives with whom they share genes.
Any colonial creature species that lives in multigenerational family bunches in which by far most of them participate to help moderately few (or even a solitary) reproductive group members are Eusocial species.
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The sun appears to cross the plane of Earth's equator
when it reaches either one of the "equinox" points in the sky.
