D. He controlled variables by studying one or two traits at a time
The organisms which appeared on earth first was bacteria.
<u>Explanation:</u>
- The first-ever living organism on Earth was a bacteria known as cyanobacteria. It is believed by scientists that it first formed around 3 billion years ago.
- When the Earth was first formed, it was inhospitable for a long time until 3.8 billion years ago approximately, the core cooled down and the level of oxygen had risen. This, along with photosynthesis resulted in the formation of Cyanobacteria.
- These organisms were capable of carrying out the process of photosynthesis by which they prepared their food. These were known as common ancestors. All the living organisms thereafter are known to be their descendants.
Answer:
Explanation:
# Boys are four times more likely to be diagnosed with autism than girls.
# Most children were still being diagnosed after age 4, though autism can be reliably diagnosed as early as age 2.
# 31% of children with ASD have an intellectual disability (intelligence quotient [IQ] <70), 25% are in the borderline range (IQ 71–85), and 44% have IQ scores in the average to above average range (i.e., IQ >85).
# Autism affects all ethnic and socioeconomic groups.
# Minority groups tend to be diagnosed later and less often.
# Early intervention affords the best opportunity to support healthy development and deliver benefits across the lifespan.
# There is no medical detection for autism.
<span>a form of natural selection in which individuals within certain inherited characteristics are more likely than others to obtain mates.</span><span>all the alleles for all the loci in all individuals of a population
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