\documentclass[11pt]{article}
% Simple LaTeX document by David J C MacKay
%                          AIMS October 2006
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%  a bibliography. 
%  See also   {\tt{/home/mackay/tex/citedemo.tex}}.
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\begin{document}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%   Title, Author, Date
\title{How High can Animals Jump?}
\author{David J. C. MacKay  --   {\tt mackay@aims.ac.za} 
%%% You can add more address details here, starting each new line with \\
}
\date{\today\ -- Draft 1.1}
\maketitle
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\begin{abstract}
 I present an explanation for why all animals can jump 
 the same height. 
\end{abstract}

\section{Introduction}
% The top speed of an  animal runnning on the 
% flat  varies with the size 
% of the animal.  
 A lion runs faster than a mouse.
 But what about jumping? 
 I once trapped a mouse behind the  bin in my kitchen.
 I was amazed to see it jump to a height of four feet. 
 With this olympic feat, the mouse got away. 
\section{Theory of jumping}
\label{secTheory}
 An animal  is mainly muscle. 
 If we assume that all animals' muscles have the 
 same physiology, we might guess that in a single big jump, 
 each little mass $\delta m$ of muscle can liberate 
 an energy proportional to  $\delta m$:
\begin{equation}
  \delta E = \lambda  \,  \delta m               ,
\label{eqDeltaE}
\end{equation}  %%    \,  inserts a small space
 where $\lambda$ is the constant of proportionality. 
 Thus the total kinetic energy of an animal with mass $m$, 
 immediately after it jumps, 
 is 
%\begin{equation}
   $E = \lambda   m $.
% \end{equation}  
 Once the animal reaches the top of its trajectory, 
 all this energy gets turned into potential energy: 
% \begin{equation}
   $E = m g h_{\max}$. 
% \end{equation}  
 So the maximum height reached  is 
\begin{equation}
   h_{\max} = \frac{ \lambda  }{ g } ,
\label{HeightEquation}
\end{equation}  
 {\em independent of the animal's size, $m$}.
 For similar reasons, while animals have different speeds
 on the flat, the top speed of an animal running up a hill
 is the same for all animals.
 For my next trick, I will explain why 
 all birds have the same flying range  -- from  seagulls
 to Boeing 747s.

\begin{figure}[h]%% using [h] forces the figure to be 'HERE'
\begin{center}
\includegraphics[width=3cm]{/home/mackay/tex/figs/balance.eps}
\end{center}
\caption{This animal has one leg and two arms.}
\label{figBalance}
\end{figure}

\section{Discussion}
 Figure \ref{figBalance} shows a picture of an animal
 juggling 4 balls.
 \citet{Shannon48} was an expert juggler. 

 Good error-correcting codes exist \citep{Shannon48}.
 I can refer to equation (\ref{eqDeltaE}) or to section \ref{secTheory}.

 You can get more help on \LaTeX\ here: 
 {\tt{http://www.aims.ac.za/resources/tutorials/latex-xfig/}}
 The source of this file is 
 {\tt{/home/mackay/tex/LatexExample.tex}}.
 My {\tt{.bib}} file is
 {\tt{/home/mackay/bibs.bib}}.
 Feel free to use these files as templates.

\bibliography{/home/mackay/bibs.bib}%%% you should put your own 
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% bib file here.
\end{document}