The Evolution of Armor in Fish: How It Contributed to Their Success in Various Watery Habitats

The Devonian Period: The Age of Fish

420 million years ago, during the Devonian Period, the Earth was a very different place. It was known as the Age of Fish, with diverse marine life including armored fish. These fish were a crucial part of the ecosystem, and their evolution of armor played a significant role in their success in various watery habitats.

Evolution of Armor for Protection and Mineral Storage

The armored fish of the Devonian Period evolved their armor not only for protection but also for storing vital minerals like calcium and phosphorous. This adaptation allowed them to thrive in different watery habitats, from shallow coastal waters to deeper ocean environments. The armor provided a defense against predators and also served as a reservoir for essential minerals, enabling the fish to survive and reproduce in a wide range of aquatic environments.

Extinction and the Rise of Bony and Cartilaginous Fish

Unfortunately, the armored fish eventually became extinct during the late Devonian mass extinctions. This event led to the disappearance of these unique creatures and paved the way for the dominance of bony and cartilaginous fish like sharks and rays in the oceans. The absence of armored fish created an ecological opportunity for other fish species to fill the niche left behind, ultimately shaping the future of marine life.

Impact on Watery Habitats

The evolution of armor in fish during the Devonian Period had a profound impact on various watery habitats. The presence of armored fish contributed to the diversity and stability of aquatic ecosystems, and their extinction triggered significant changes in marine life dynamics. The disappearance of armored fish allowed for the rise of new fish species, leading to the development of modern oceanic ecosystems as we know them today.


In conclusion, the evolution of armor in fish during the Devonian Period was a crucial factor in their success in various watery habitats. The armor provided protection and mineral storage, enabling these fish to thrive in diverse aquatic environments. While the extinction of armored fish marked the end of an era, it also set the stage for the emergence of new marine life forms, shaping the future of ocean ecosystems.

Leave a Comment