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\begin{document}

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\title{Le Grizzly}
\author{Grizzly \& Chouca}
\date{24 Janvier 1997}
%thanks{Le mec qui fait le cafe}

\maketitle

\begin{abstract}
Ceci est l'abstract de mon article sur les Grizzly à Cachan. Si on fait un abstract plus long on se rend compte qu'il est centré sur la page mais que ses marges sont plus grandes que celle du corp de l'article. L'abstract est le premier (ou plutot deuxieme si l'on compte le document en lui même) exemple d'utilisation d'un environement dans ce tutoriel.
\end{abstract}

\section{Grizzly bear}
The grizzly bear (Ursus arctos ssp.) is a large population of the brown bear inhabiting North America. Scientists generally do not use the name grizzly bear but call it the North American brown bear.

\begin{warning}[red]{Grizzly Cub}
If you encounter Grizzly cubs, do not try to approach them. The safest option is to back up without presipitation. The Grizzly mother if eager to run after you if she thinks her cubs are in danger.
\end{warning}

\begin{enumerate}[(I)]
\item For back-country campers, hanging food between trees at a height unreachable to bears is a common procedure, although some grizzlies can climb and reach hanging food in other ways. An alternative to hanging food is to use a bear canister.


\begin{center}
\begin{tabular}{lcr}%{|l|c|r|}
Location & Populaion & Estimate in 2020 \\
\hline
North Cascades Ecosystem & 20 & 30 \\
Selkirk Mountains Ecosystem & 75 & 70 \\
Cabinet Yaak Ecosystem & 45 & 45 \\
Northern Continental Divide Ecosystem & 765 & 800 \\
Bitterroot Recovery Ecosystem & 0 & 10 \\
Yellowstone & 650 & 650 \\
\end{tabular}
\end{center}


\item Grizzly bears are especially dangerous because of the force of their bite, which has been measured at over 8 megapascals (1160 psi). It has been estimated that a bite from a grizzly could even crush a bowling ball.
\end{enumerate}

\section{Classification}
\subsection{Meaning of "grizzly"}
Meriwether Lewis and William Clark first described it as grisley, which could be interpreted as either "grizzly" (i.e., "grizzled"—that is, with golden and grey tips of the hair) or "grisly" ("fear-inspiring", now usually "gruesome").

\begin{align*}
	&\int_R^{+\infty} p(t)dt = \frac{\pi}{2}\\
    &\lim_{n\rightarrow \infty}\sum_{n=0}^N=4
\end{align*}


The modern spelling supposes the former meaning; even so, naturalist George Ord formally classified it in 1815 as U. horribilis, not for its hair, but for its character.


\begin{description}
	\item [Biologie] Science du vivant
	\item [Géologie] Science du caillou
\end{description}


\subsection{Appearance}
Most adult female grizzlies weigh 130–180 kg (290–400 lb), while adult males weigh on average 180–360 kg (400–790 lb). Average total length in this subspecies is 198 cm (6.50 ft), with an average shoulder height of 102 cm (3.35 ft) and hindfoot length of 28 cm (11 in). We can see a Grizzly walking in the forest on figure \ref{fig:grizzly}.\\

\begin{figure}[h]
	\centering
	\includegraphics[width=0.8\linewidth]{images/grizzly.png}
	\caption{This is a Grizzly}
	\label{fig:grizzly}
\end{figure}

Although variable in color from blond to nearly black, grizzly bear fur is typically brown with darker legs and commonly white or blond tipped fur on the flank and back. A pronounced hump appears on their shoulders; the hump is a good way to distinguish a grizzly bear from a black bear, as black bears do not have this hump. Aside from the distinguishing hump a grizzly bear can be identified by a "dished in" profile of their face with short, rounded ears, whereas a black bear has a straight face profile and longer ears. A grizzly bear can also be identified by its rump, which is lower than its shoulders, while a black bear's rump is higher. A grizzly bear's front claws measure about 2–4 inches in length and a black bear's measure about 1–2 inches in length.

\newpage

Meat, as already described, is an important part of a grizzly's diet. Grizzly bears occasionally prey on small mammals, such as marmots, ground squirrels, lemmings, and voles. The most famous example of such predation is in Denali National Park and Preserve, where grizzlies chase, pounce on, and dig up Arctic ground squirrels to eat.

\begin{wrapfigure}[21]{l}[0cm]{0.3\textwidth}
\centering
\includegraphics[width=0.8\linewidth]{images/fishing.jpg}
\caption{A Grizzly fishing}
\label{fig:fishing}
\end{wrapfigure}

In some areas, grizzly bears prey on hoary marmots, overturning rocks to reach them, and in some cases preying on them when they are in hibernation. Larger prey includes bison and moose, which are sometimes taken by bears in Yellowstone National Park. Because bison and moose are dangerous prey, grizzlies usually use cover to stalk them and/or pick off weak individuals or calves. Grizzlies in Alaska also regularly prey on moose calves, which in Denali National Park may be their main source of meat. In fact, grizzly bears are such important predators of moose and elk calves in Alaska and in Yellowstone, that they may kill as many as 51 percent of elk or moose calves born that year. Grizzly bears have also been blamed in the decline of elk in Yellowstone National Park when the actual predators were thought to be gray wolves. In northern Alaska, grizzlies are a significant predator of caribou, mostly taking sick or old individuals or calves. Several studies show that grizzly bears may follow the caribou herds year-round in order to maintain their food supply. In northern Alaska, grizzly bears often encounter muskox. Despite the fact that muskox do not usually occur in grizzly habitat and that they are bigger and more powerful than caribou, predation on muskox by grizzlies has been recorded. Grizzly bears along the Alaskan coast also scavenge on dead or washed up whales. Usually such incidents involve only one or two grizzlies at a carcass, but up to ten large males have been seen at a time eating a dead humpback whale. Dead seals and sea lions are also consumed.

\section{Commandes personnalisées}
Sans la commande personnalisée:

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	F' = \dfrac{ \partial f}{\partial t}
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Avec la commande:

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	F' = \dpart{f}{t}
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\begin{align*}
	F' &= \dpart{f}{t}\\
	F' &= \dpart[3]{f}{t}\\
	F' &= \dpart[plop]{f}{t}\\
\end{align*}

\section{Environements personnalisées}







\end{document}