Town and city birds have bigger brains than country cousins
And the reason is having to fit in with the mod cons of a human environment has boosted their health and intelligence.
This includes learning how to open drawers to get to food and developing bolder behaviour than they would in a rural area with fewer people.
In the first study of its kind scientists found urban birds have the edge by needing to adapt to exploit new resources .
They identified clear differences in problem solving abilities such as associative learning, linking a cure to a particular outcome, and innovative problem solving which is considered to be even more useful in the 'real life' of wild animals.
Jean-Nicolas Audet, a PhD student at McGill University, Montreal, said: "We found not only were birds from urbanized areas better at innovative problem solving tasks than bullfinches from rural environments, but surprisingly urban birds also had a better immunity than rural birds.
"Since urban birds were better at problem solving, we expected there would be a trade off and the immunity would be lower, just because we assumed you can't be good at everything'. In fact, both traits are costly. It seems in this case, the urban birds have it all."
The study published in the journal Behavioral Ecology analysed bullfinches captured from various parts of the Caribbean paradise of Barbados.
Audet explained: "The island of Barbados shows a strong range of human settlement, there are some very developed areas but also mostly left untouched, thus providing an excellent environment to study the effects of urbanisation."
Tasks included putting the birds in cages and testing their ability to open drawers to access food, as well as how bold or confident they were with the human researchers.
This revealed key differences in the abilities and temperament among city birds versus country as well as their immunity - with the former first in the pecking order for both.
Audet and his fellow researchers tested more than 50 Barbados bullfinches captured from various parts of the Caribbean island - some from urban environments, others from wild areas mostly left untouched.
The urban birds proved to be smarter, bolder and healthier than those in rural areas.
Audet said he was inspired after being hounded by the birds at a restaurant terrace in Barbados.
He said: "Barbados bullfinch are always watching and trying to steal your sandwich. I was really interested in studying how they develop this way in cities."
The team of three researchers spent months at McGill's Bellairs Research Institute in Barbados carrying out their experiments.