Is there an incompatibility between `eulervm` and `fourier` packages?

Question

In the following minimal document

\documentclass{article}
\usepackage{fourier,eulervm}
\begin{document}
$1 < 2$
\end{document}

the output is missing the < symbol.

On the other hand, if I load the two font packages in the opposite order

\documentclass{article}
\usepackage{eulervm,fourier}
\begin{document}
$1 < 2$
\end{document}

the output is as it should. Why?

I could not find this documented anywhere.

Added

A less minimal example would also show that whereas in the latter case the < does appear, the math fonts being used are not the Euler fonts. Hence I do think that the two are incompatible. I'm starting to think that perhaps incompatibility between different font packages is the norm and not the exception?

Answer 1

Both packages mess around with the maths font loading, so you'd generally expect problems to arise loading them together. What are the combinations of fonts you're trying to use?