[2] The first movement is notable for having the main theme based on the repeated note short-short-short long which echoes the rhythm of the Fate motif of Beethoven's Fifth symphony.
[3] Larry Todd states that: The first movement appropriates its familiar four-note head motive from Beethoven's Fifth Symphony.
The first movement is fairly saturated with the motive, which appears in the first theme, the bridge and the closing section of the exposition.
In particular, Todd argues that Strauss' Adagio Cantabile is effectively a Mendelssohnian Lied ohne Worte (Song without words).
[5] In the Scherzo and Finale, one can also find echoes of Mendelssohn, both in terms of structure, time signature and thematic material.