Darwin noticed that birds that were good at finding scarce food in the winter had a better chance of surviving and producing offspring. What did he call this struggle for existence?

How are genomics and DNA improving the production of livestock?

The rod cells in the retina contain a light-absorbing pigment called a. melanin. b. melatonin c. iodopsin. d. rhodopsin

What biomes are found in south africa

Joshua needs to clean his dog every week to remove the ticks from the dog's body. What kind of interaction do Joshua's dog and the ticks have? A. parasitism B. mutualism C. interference competition D. predation

Why does the level of progesterone and oestrogen remain highly during pregnancy?

How do dolphins adapt to their habitat

Which is larger? 1 millimiter or 1 centimeter

All information recorded on the PCR must be: Select one: a. typewritten or printed. b. considered confidential. c. a matter of public record. d. reflective of your opinion.

Which of the following do all vertebrates have in common? More than one answer is possible. A. mammary glands B. cranium C. vertebral column D. specialized teeth

It takes a lot of energy to change the temperature of water. This is important for both aquatic organisms and the Earth's weather and climate patterns.