Answer:
Nucleotide, Gene, DNA, Chromosome, Cell.
Explanation:
Fossils , silicone just guessed sorry
The right answer is decreased nonshivering thermogenesis.
The increase in metabolism allows an increase in the production of heat. Newborns use their brown fat as a source of heat, it is a non shivering thermogenesis.
The second mechanism for increasing heat in humans is increased muscle tone and shivering, but in the newborn there is no chill.