I keep getting excessive whitespace between columns in my graphs:
\documentclass{article}
\usepackage{array}
\usepackage{siunitx}
\usepackage{booktabs}
\usepackage[flushleft]{threeparttable}
\usepackage[T1]{fontenc}
\newcommand{\M}[1]{\multicolumn{1}{l}{#1}}
\newcommand{\C}[1]{\multicolumn{1}{c}{#1}}
\begin{document}
%summary statistics
\begin{table}[!ht]
\centering\setlength\extrarowheight{2pt}
\begin{threeparttable}
\begin{tabular}{@{\extracolsep{0pt}}cccc*{2}{SSSS}}
\toprule
\C{Behavior} & \C{Sex Ratio} & \multicolumn{3}{c}{Incidence} & \multicolumn{3}{c}{Duration (s)}\\
\cmidrule(lr){1-1}
\cmidrule(lr){2-2}
\cmidrule(lr){3-5}
\cmidrule(lr){6-8}
\M{Type} & \C{F:M} & \C{Mean} & \C{${\pm}$} & \C{SEM${^\dagger}$} & \C{Mean} & \C{${\pm}$} & \C{SEM${^\dagger}$} \\
\midrule
\\[-2.0ex]
\M{Probing}\\
\\[-1.8ex]
\M{A} & 0.84 & \multicolumn{1}{S}{1.3} & ${\pm}$ & 0.13 \ {a} & 260.0 & ${\pm}$ & 12.0 \\
\M{B} & 1.29 & \multicolumn{1}{S}{1.5} & ${\pm}$ & 0.13 \ {a} & 260.0 & ${\pm}$ & 12.0 \\
\M{C} & 1.39 & \multicolumn{1}{S}{1.8} & ${\pm}$ & 0.16 \ {a} & 250.0 & ${\pm}$ & 11.0 \\
\M{D} & 1.44 & \multicolumn{1}{S}{2.8} & ${\pm}$ & 0.38 \ {b} & 270.0 & ${\pm}$ & 6.0 \\
\bottomrule
\end{tabular}
\end{threeparttable}
\end{table}
%ANOVA table
\begin{table}[!htbp]
\centering\setlength\extrarowheight{2pt}
\caption{Wald's ${\chi^2}$ tests}
\label{tab:tbl_1}
\begin{threeparttable}
\begin{tabular}{@{\extracolsep{0pt}}ccc*{2}{SSSSSSS}}
\toprule
\M{Behavior${^\dagger}$} & \multicolumn{3}{c}{Incidence} & \multicolumn{3}{c}{Duration}\\
\cmidrule(l){0-0}
\cmidrule(l){2-4}
\cmidrule(l){5-7}
\M{Factors} & \C{${\chi^2}$} & \C{df} & \C{Pr \ ${>}$ \ ${\chi^2}$} & \C{${\chi^2}$} & \C{df} & \C{Pr \ ${>}$ \ ${\chi^2}$} \\
\midrule
\\[-2.0ex]
\M{Probing} \\
\\[-2.0ex]
\M{Variety} & \multicolumn{1}{S}{27.46} & \C{3} & \C{0.000} & 2.51 & \C{3} & \C{0.473} \\
\M{Sex} & \multicolumn{1}{S}{3.24} & \C{1} & \C{0.072} & 0.00 & \multicolumn{1}{c}{1} & \C{0.959} \\
\M{Variety ${\times}$ Sex} & \multicolumn{1}{S}{6.49} & \C{3} & \C{0.090} & 4.74 & \C{3} & \C{0.192} \\
\bottomrule
\end{tabular}
\end{threeparttable}
\end{table}
\end{document}