Drivers of individual differences in the sleep behaviour of fallow deer neonates

Inter-individual differences are necessary for selection to act, while plasticity (intra-individual variation) may buffer against selection. Sleep is a critical self-maintenance behaviour but, unlike most behaviours, the causes and consequences of its inter- and intra-individual variation in wild animals is poorly understood, particularly in neonates where sleep plays a key role in development. We have shown previously that free-ranging neonate fallow deer (Dama dama) differ in sleep during the first few weeks of life. Here, we test whether individual variability in sleep is organised systematically across the population, and whether these individual differences are associated with chronic stress measured using hair cortisol, or the timing of birth. Four dimensions of sleep behaviour (total sleep time, sleep fragmentation, sleep quality, and sleep distribution over 24-hours) were quantified using state-of-the-art triaxial accelerometers. We then used a multivariate mixed-effects model i..., , , # Drivers of individual differences in the sleep behaviour of fallow deer neonates

[https://doi.org/10.5061/dryad.4qrfj6qmt](https://doi.org/10.5061/dryad.4qrfj6qmt)

## Description of the data and file structure

### Files and variables

#### File: manuscript\_data.csv

##### Description:

##### Variables

* tst_mins: total minutes slept for that date and individual
* age_days_scaled: age in days (centered and scaled) for that date and individual
* temp_c_scaled: mean temperature in degrees C (centered and scaled) for that date
* birthdate_jd_scaled: birth date in julian days for that individual
* cort_pgmg_scaled: hair cortisol measure in pg/mg for that individual
* animal_id: unique animal ID
* year: data collection year
* ds_pct: distribution of sleep, the % of total sleep occurring between sunrise and sunset for that date and individual
* bouts: total number of sleep bouts for that date and individual
* longest: duration of longest sleep bout in minutes for that date and individua...