in at 2.52 kg and the male at 3.17 kg. Another study in 1992 found that the female weighed 2.51 kg, while the male weighed 3.02 kg. Then one of the more recent studies in 2009 identified the female weight to be roughly 2.56 kg with the male weighing in at 3.06 kg. In terms of length, the head and body combined measurements for the male and female were measured across two studies. The first measured 39.5 cm for females and 40.2 cm for males, while the other measured females at 41.8 cm and males at 42.7 cm. Generally, their body measurements and weight, in combination with their tails for balance and support, makes them "agile and fast-moving" and "super climbers and leapers". Behaviours Social behaviours The white-nosed saki are a diurnal species who engage in various activities during the day through the formation of groups which is their main system of socialisation. These groups have been found to consist of 19–30 individuals of both males and females. Their grouping is referred to as a "fission-fusion" system which involves them coming together for sleeping or food gathering, and then separating throughout the day for other activities. Although they group together and rely on each other for many of these reasons, they have very few means of communication with one another. Those that they do use are all based on sound and often occur only while performing certain activities together where cooperation is important. For example, they are louder and use a higher pitch "alarm call" for getting each other’s attention generally, or during times of danger, but use more of a lower pitch during points where they are concentrated on a specific task such as relaxing or eating. They do also use some visual communication forms, with the main one being "tail wagging" used to show confusion. In general, although they communicate in some ways with one another, they have been described as a shy species when it comes to social interaction and behaviour. Although a few different interactions have been observed, it has been claimed that the intended meaning behind these calls remains under researched. Anti-predator behaviours Predation has a big impact on the way that the white-nosed saki conducts their everyday lives when it comes to "social organisation", "foraging strategies", choosing "sleeping site[s]" and then deciding on how much time is spent on each of these activities. Their