Final answer:
The diversity and complexity of living things have increased over time, shaped by the process of evolution. Evidence of change and increasing complexity is found in the fossil record, molecular data, and continual refinement of taxonomies. Advancements in technology further our understanding of the vast biodiversity that exists.
Step-by-step explanation:
The complexity and diversity of living things has significantly increased over time due to the process of evolution. As evolution occurs, new species arise from older ones, contributing to the vast biodiversity we observe today. From single-celled organisms to complex multicellular ones, life on Earth encompasses a wide array of plants, animals, fungi, bacteria, and archaea. This immense variability is the result of natural processes, evolutionary changes, and advances in scientific technology that help classify and understand life more accurately.
Key evidence of this evolution includes the fossil record, molecular data, and the ongoing reevaluation of the taxonomy of living organisms as technology improves. Evolution shapes the structure of the tree of life, which is continually refined and contributes to our understanding of biodiversity. However, despite advancements in technology and knowledge, the magnitude and complexity of this biodiversity pose a significant challenge to fully comprehending every aspect of life's variation and history.
Conclusively, the theory of evolution, supported by various scientific evidence such as fossiles and molecular data, outlines that biodiversity has been and continues to be shaped by a myriad of natural factors over time, leading to an ever-increasing complexity and variety of life forms.