Do men really prefer big, perky breasts? Guys across the globe reveal what they're into when it comes to breast size and shape.Women's breasts come in all sizes and shapes. They vary in terms of how big - or small - they are, their shape, from perky to sagging, and whether or not they're symmetrical.With our cousins, the apes and monkeys, the females' breasts only enlarge during pregnancy and breast feeding. But women's breasts are enlarged... well, permanently. Many a scientist out there has wondered why this might be. One possible explanation is that over time men came to prefer big, perky breasts because they were a sign that a woman was fertile.Best-loved breast sizeThough plenty of studies have looked at men's preferences for breast size, there's been no hard evidence that bigger is better. And when it comes to perkiness, there's simply been no research done.So a group of researchers from across the globe got together with the aim of finding some answers. First, they tracked down over 250 guys from Brazil, Cameroon, the Czech Republic, and Namibia. This was probably not that difficult to do: the guys' task was to look at pictures of breasts and rate how attractive they were. The breasts in the pictures varied in terms of size (small, medium, and large) and firmness (high, moderate, rather low, and low).So what were the best-loved breasts in the test? When it comes to breast size, bigger is not necessarily better, the results showed. Though most guys chose medium-sized breasts (with big busts ranking second), there was a lot of variation from one participant to the next. This was true in all four countries. With the exception of the Czech Republic, up to about one in five guys in each country preferred women with small breasts. Other research has backed up these results: around the world, studies have found that guys are attracted to all different sizes of breasts. Read more on Love Matters website