Constant Temperature Equivalent (CTE)

An R package for calculating the Constant Temperature Equivalent (CTE) for nest incubation data

Descritpion

This package provides a simple function (CTE) for calculating CTE based on the formulas developed in Georges A (1989) Female turtles from hot nests: is it duration of incubation or proportion of development at high temperatures that matters? Oecologia 81:323–328.

See the vignette for full details on the formulas and search algorithms.

Installation

Copy and paste the code below to install the package

install.packages("devtools") #Installs devtools (if not already installed)
devtools::install_github("donaldtmcknight/CTE") #Installs CTE

Running the package

The pacakge includes a single function: CTE.

It requires three pieces of data:

• M = mean temperature
• R = the maximum deviation of temperatures from M (e.g., if the range of temperatures is 14‒16 and M = 20, then R = 6)
• T₀ = the temperature below which no development occurs (this value should be based on a general knowledge of the species being studied)

You can optionally include t, a vlue between 0 and 2pi which sets the starting seed for the iterative calcuations, and max.it, which sets the maximum number of iterations the function will try (default is 10,000).

Example:

CTE(M=20, R = 6, T0=10)

Citaiton

Cite as: McKnight, D.T. 2026. CTE: Constant Temperature Equivalent. R package version 0.1.0