A group of Australian scientists have claimed that they have been successful in finding a 'causal link' between the human-induced global warming and early emergence of butterflies.

According to researchers, led by Dr. Michael Kearney of the University of Melbourne, the findings of the study have given scientists, for the first time ever, concrete evidence that there is a direct influence of greenhouse gases on the timing of a natural event.

The team of scientists found that with an average of 1.6 days per decade over a 65 year span, the Common Brown butterfly has emerged earlier, constantly on a yearly basis.

Dr. Kearney says, "It's now coming out about 10 days earlier than it was 60 years ago. When you look at the air temperatures over that time, it's getting warmer".

"Its causal all the way through, the warmer it is, the faster they will emerge", he explained.

Dr. Kearney tells that the local Wurundjeri Aboriginals have defined the beginning of one of their seasons, as per their tradition, when they see a male common brown butterfly emerging.

The research, which is part of a project, funded by Australian Research Council, will be published in this week's Royal Society journal Biology Letters.