What object would best be identified by a periodic doppler shift in a star's spectrum along with a dip in the star's light intensity?

What are the steps of how energy is transformed in plant cells?

What are some things that limit population growth?

Amale bird-of-paradise uses a dance to attract mates in which it flaps its tail feathers on the ground and jumps around a potential female mate. a different male bird-of-paradise does a similar dance but it jumps around the female in the opposite direction. the female bird is only attracted to one style of dance, in one direction.