We hear a lot about race these days and it's the fuel for a lot of hatred around the world today. But what is race? Well, race today is still defined in many ways and I think this only goes to show that there is still much widespread disagreement on the matter, there is an undetermined consensus as to whether it is in fact a social construct or a biological one.
It has been argued by many that race isn't defined by the way that people look because there is no objective criteria to go about choosing an adaptive trait (like skin color) over another in order for you to be able to define race; adaptive traits don't define races. Many scientists, psychologists, and other academic experts, have reaffirmed the notion that the human race does have a vast amount of genetic diversity but the diversity which exists isn't due to “race”, but rather it's a reflection of individual uniqueness.
Some people get readily confused hearing the premise that race may be a social construct because they take it to mean you are saying that there are no obvious visible differences to be seen (for the majority) from people who come from differing locations. But that isn't what is being said. Lumping people quickly into groups based on what their skin color or hair color is ignores the vast amount of human diversity that exists. There might be differing tribes and cultural differences but that doesn't support the notion of race as a biological construct.
Some talk about race in the way of certain groups being more susceptible to illness than others, or they will use identifying critique like intelligence tests, but that doesn't translate into a gene or cluster of genes that can be identified as being common to every single individual from every racial group. Not one gene can be used to distinguish and identify all members of one so-called race from all members of another so-called race.
A couple of years ago the U.S. National Academies of Sciences, Engineering, and Medicine, put together a panel of experts who sought to shift away from racial concepts in genetic research because they believe that racial categories are weak proxies for genetic diversity. It appears that the majority-held view within the scientific community is still that race is a social construct.
At present, many scientists and others still argue that there is no biological validity to racial classification. Grouping together people based on their skin color, eye shape, hair texture or hair color etc, isn't a biological validation. If we want to go off just what people look like, in order to lump them into a category, then quite often we can be very easily misled as to what a person actually identifies with and what their heritage is. Therefore race cannot be determined in this way.
Science:
http://www.ncbi.nlm.nih.gov/pubmed/23684745
http://www.scientificamerican.com/article/race-is-a-social-construct-scientists-argue/