A dataset containing experimental results on hatching behavior of red-eyed tree frog embryos.

Red-eyed tree frog (RETF) embryos can hatch earlier than their normal 7ish days if they detect potential predator threat. Researchers wanted to determine how, and when, these tree frog embryos were able to detect stimulus from their environment. To do so, they subjected the embryos at varying developmental stages to "predator stimulus" by jiggling the embryos with a blunt probe. Beforehand, though some of the embryos were treated with gentamicin, a compound that knocks out their lateral line (a sensory organ.) Researcher Julie Jung and her crew found that these factors inform whether an embryo hatches prematurely or not!



A data frame with 1212 rows and 6 variables:


RETFs lay their eggs in gelatinous "clutches" of 30-40 eggs. Eggs with the same clutch ID are siblings of each other! This variable is useful in mixed effects models. (Unordered factor.)


The treatment group for the embryo. Either "gentamicin", a compound that knocks out the embryos' lateral line, or "control" for the negative control group (i.e. sensory organs intact). (Character.)


A measure of ear function called the vestibulo-ocular reflex, categorized into bins. Ear function increases from factor levels "low", to "mid", to "full". (Ordered factor.)


Age of the embryo, in seconds, at the time that the embryo was jiggled. (Numeric, in seconds.)


The time of day that the stimulus (i.e. jiggle) was applied. "morning" is 5 a.m. to noon, "afternoon" is noon to 8 p.m., and "night" is 8 p.m. to 5 a.m. (Character.)


Whether or not the embryo hatched in response to the jiggling! Either "yes" or "no". (Character.)


Time elapsed between the stimulus (i.e. jiggling) and hatching in response to the stimulus, in seconds. Missing values indicate that the embryo didn't hatch in response to the stimulus. (Numeric, in seconds.)




Note that the data included with the stacks package is not necessarily a representative or unbiased subset of the complete dataset, and is only for demonstrative purposes.