original_query: What were Charles Darwin's investigations between 1873 and 1882?
query: What were Charles Darwin's investigations between 1873 and 1882?
answer: Between 1873 and 1882, Darwin's investigations included work on climbing plants, insectivorous plants, the effects of cross and self-fertilization of plants, different forms of flowers on plants of the same species, the power of movement in plants, and earthworms' effects on soil formation. He also revised several of his books and continued his correspondence and funding of various scientific projects.  His work was interwoven with family matters, religious conflicts, and participation in public debates.