According to Beatty (1986), population genetics defines the core of the modern synthesis. In the first few decades of the 20th century, most field naturalists continued to believe that Lamarckian and orthogenic mechanisms of evolution provided the best explanation for the complexity they observed in the living world.
The Netherlands has been a constitutional monarchy since 1815 and a parliamentary democracy since 1848. Previously, it was a republic from 1581 to 1806, and a kingdom between 1806 and 1810 (it was part of France between 1810 and 1813).
The Netherlands is fully part of the European Union. This means that a citizen of the Netherlands is also a citizen of the EU, and can travel and reside freely in any of the member states of the EU. Dual citizenship is permitted but on a limited basis.