Final answer:
The correct answer is Schleiden, but another German scientist who studied animals is Ernst Haeckel.
Step-by-step explanation:
Schleiden is the correct answer to the question. Matthias Schleiden was a renowned German scientist who studied plants, not animals. Another German scientist from the 1800s who studied animals is Ernst Haeckel. Haeckel made significant contributions to the field of zoology, particularly in the study of marine organisms and the development of evolutionary theory.
Learn more about German scientists studying animals in the 1800s