XXXY syndrome

a relatively rare disorder in which a male inherits the full complement of both male and female sex chromosomes instead of either the normal two X chromosomes (46, XX) for females or the normal one X and one Y chromosome (46,XY) for males. Affected individuals have a normal penis but small testes and prostate, and about half develop enlarged breasts and have intellectual and developmental disabilities. Also called 48,XXXY syndrome.

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Psychology term of the day

February 16th 2025

sun compass

the use of the sun as a directional stimulus in orientation and navigation. Because the sun appears to move across the sky during the day and has different trajectories in different seasons, a sun compass must be coupled with some form of time estimation. To head south at 9 a.m., one needs to keep the sun on the left, but at 3 p.m., one needs to keep the sun on the right. Studies of several species, ranging from bees to fish and birds, have demonstrated a time-compensated sun compass. For nocturnal species, there is evidence of a star compass.