When it comes to having sex, dinosaurs didn't have to wait until they were fully grown to start mating. Rather, they preferred to mate quite early in their teenage.

A latest research by American palaeontologists has found that bird-like dinosaurs reached sexual maturity earlier than their physical features were developed and until engaged in the sexual activity early in their youths.

Since the dinosaurs have all bird-like symptoms like sitting on eggs, sleeping, and even have bone structures like birds, scientists initially thought that these reptiles also reproduced like birds.

However, scientists now say that this is not the case with dinosaurs, which did not wait until they were fully grown to start having sex.

National Geographic News quotes Kristina Curry Rogers, a palaeontologist at the Science Museum of Minnesota in St. Paul, and co-author of the study as saying that by mating early, dinosaurs are "really holding on to their ancestry, rather than jumping into the modern-bird style of reproduction."

The recent discovery shows that the present day birds did not inherit all the features from their dinosaur precursors but only a part of their traits. The study, published last month in the online edition of the journal Biology Letters, shows fast growth and delayed sexual maturity came late in the history of bird evolution.

Scientists now say they will focus on a new series of study that will search about the traits that makes the birds stand apart from dinosaurs.