True or false? New major animal body plans have continued to evolve since the Cambrian about 550 million years ago.

Verified step by step guidance

1. Understand the context of the Cambrian period: The Cambrian period, occurring about 540 million years ago, is known for the 'Cambrian Explosion,' a time of rapid diversification in animal life where many major animal groups (phyla) first appeared in the fossil record.
2. Define 'major animal body plans': Major animal body plans refer to the fundamental structural architectures of animals, categorized into different phyla based on characteristics such as body symmetry, segmentation, and limb disposition.
3. Evaluate evolutionary changes post-Cambrian: After the Cambrian period, while there have been many evolutionary changes and adaptations within these phyla, no fundamentally new major animal body plans have emerged. Evolution has mostly involved diversification within the established phyla.
4. Consider the evidence from paleontology: Fossil records post-Cambrian show adaptations and speciation within existing phyla but do not indicate the emergence of new phyla with distinct, new body plans.
5. Conclude the statement: Based on the understanding of what constitutes a 'major animal body plan' and the evidence from fossil records, the statement is false. New major animal body plans have not continued to evolve significantly since the Cambrian period.

Key Concepts

Cambrian Explosion

The Cambrian Explosion refers to a significant period in Earth's history, around 541 million years ago, when a rapid diversification of life forms occurred. This event led to the emergence of most major animal phyla and established the foundational body plans that characterize modern animals. Understanding this period is crucial for evaluating the evolution of body plans over time.

Evolutionary Biology

Evolutionary biology is the study of the processes that drive the diversity of life on Earth, including natural selection, genetic drift, and speciation. It provides the framework for understanding how new traits and body plans can arise and adapt over time. This concept is essential for assessing whether new major body plans have emerged since the Cambrian.

Body Plans

Body plans refer to the structural organization of an organism, including its symmetry, segmentation, and the arrangement of its organs. Major animal body plans, such as bilateral and radial symmetry, have been foundational in the classification of animals. Recognizing how these plans have evolved or remained stable is key to answering questions about the continuity of evolution since the Cambrian.