The answer is relative dating.
Mutation. this happens when a cell copies its DNA to divide. its more common than you may think, a "typo" occurs every 100, 000 or so nucleotides, thats about 120, 000 "typos" every time a cell divides.
9:3: 3:1 is the phenotypic ratio showing traits as black and long hair : black and short hair: chestnut and long hair: chestnut and short hair when a chestnut horse heterozygous for pacing and hair length with a hybrid horse.
Explanation:
Dominant trait = black hair colour (BB,Bb), trotting (TT,Tt) , long hair (LL,Ll)
recessive trait = chesnut hair colour (bb), pacing gait (tt), short hair(ll)
cross between chestnut horse heterozygous for pacing and hair length will have alleles as BbLl
alleles for hybrid horse will also be heterozygous Bb, Ll
Punnett square to show the cross:
BL Bl bL bl
BL BBLL BBLl BbLL BbLl
Bl BBLl BBll BbLl Bbll
bL BbLL BbLl bbLL bbLl
bl BbLl Bbll bblL bbll
phenotype ratio
black and long hair : black and short hair: chestnut and long hair: chestnut and short hair
9:3: 3:1 is the phenotype ratio.
Correct answer: B). Shelter wood cutting takes place over several years
Shelterwood cutting is the progressively cutting of the forest, in order to establish the growth of the new generation of the seedlings of a particular species without planting.
It is a method of natural tree reproduction under the shelter of old trees, which are removed successively by cutting the tree in order to provide the increased amount of light to the new seedlings. It is a slow process and takes lot of time.