Looking at any population of living organisms, we see differences - people on the street look different from each other, University of Otago zoology Distinguished Professor Hamish Spencer says.
"Cats do too. Even creatures with which we are less familiar - snails, birds, insects - show variation, as, of course, do plants.
"Why do we look the way we do?"
It is called the "paradox of variation" and it is a huge question - one Prof Spencer hopes to answer with the aid of a Royal Society of New Zealand James Cook Research Fellowship.
The fellowship is worth $100,000 annually (plus $10,000 for relevant expenses) and is for researchers at the height of their careers, allowing them to undertake study or research in their field for two years.
Prof Spencer is one of three in New Zealand to receive the award.
He is an evolutionary biologist and uses mathematical modelling and molecular genetics to understand the processes driving the evolution of the world’s broad biodiversity.
"To some degree, these differences reflect genetic differences among individuals.
"This heritable variation is at the heart of evolution, as Darwin pointed out.
"Natural selection accentuates these differences to bring about evolutionary change; without any genetic differences, evolution doesn’t happen."
He said genetic differences were also critical to artificial selection.
"Different dog breeds, for example, have come about because of the genetic differences underlying the various traits that dog breeders favoured.
"Yet, we do not know why these populations have all this variation - although it is originally generated by mutation.
"We do not know if it is preserved by natural selection or whether it is neutral, irrelevant to current selection pressures."
That distinction mattered, he said.
"If the variation is preserved by selection, it is likely that more variable populations are healthier, a conclusion that concerns many science users, from animal breeders to conservation managers of threatened species.
"Clearly, answering this question is important and yet, it has been an unanswered central question in evolutionary genetics for over 50 years."
Using new mathematical models in conjunction with computer simulations, he planned to enhance understanding of how evolutionary processes interacted with each other and how this shaped genetic variation.
"This research will improve what are currently overly simplistic genetic models and explain the levels of genetic variation seen in nature.
"A resolution of the paradox of variation will have implications for fundamental evolutionary biology to numerous applications in agriculture, conservation, medicine and beyond," he said.
