How does the trilobite provide evidence for evolution?

Because they evolved rapidly, and moulted like other arthropods, trilobites serve as excellent index fossils, enabling geologists to date the age of the rocks in which they are found. Abundance: Trilobites are very well-known, and possibly the second-most famous fossil group after the dinosaurs.

What type of evolution is evident in trilobites?

We show that trilobites have a Cambrian origin, as supported by the trace fossil record and molecular clocks. Surprisingly, they exhibit constant evolutionary rates across the entire Cambrian, for all aspects of the preserved phenotype: discrete, meristic, and continuous morphological traits.

What evolved from trilobites?

Trilobites have no known direct descendants. Their closest living relatives would be the chelicerates due to both being arachnomorphs. Though horseshoe crabs are often cited as their closest living relatives, they are no closer evolutionarily than other chelicerates.

What are 2 important facts about trilobites?

Trilobites were the first group of animals in the animal kingdom to develop complex eyes. Cambrian Period (about 500 million years ago). Trilobites lived in marine waters. Some trilobites could swim, others burrowed or crawled around on muddy sea floors.

What is special about trilobites?

Their amazing diversity has made them the stratigraphic marker of the Cambrian Period, as well as allowing them to play a key role in estimating the rate of speciation during the Cambrian explosion. Trilobite studies have resulted in formulating and testing Punctuated Equilibrium as an evolutionary mechanism.

What could explain the presence of trilobite fossils in such diverse parts of the world?

What could explain the presence of their fossils in such diverse parts of the world? If the continents had been connected to each other at one time, then the area where trilobites would have lived would not be as large an area and it would be possible for trilobites to spread across the region over time.

What special body features did trilobites evolve?

Trilobites had three body lobes, two of which lay on each side of a longitudinal axial lobe. The trilobite body was segmented and divided into three regions from head to tail: the cephalon, or head region, separated from the thorax, which was followed in turn by the pygidium, or tail region.

What are three characteristics of trilobites?

The trilobite body is divided into three tagmata (major sections), a cephalon with eyes, mouthparts and antennae, a thorax of multiple articulated segments (that in some species allowed enrollment), and a pygidium, or tail section of fused segments.

When did trilobites evolve?

521 million years ago
These ancient arthropods filled the world’s oceans from the earliest stages of the Cambrian Period, 521 million years ago, until their eventual demise at the end of the Permian, 252 million years ago, a time when nearly 90 percent of life on earth was rather suddenly eradicated.

Why are trilobites so important?

Geologists use trilobites in a variety of ways to help them understand how the Earth has developed. One use is in the relative dating and stratigraphical correlation of sedimentary rock successions, especially in rocks of Cambrian and early Ordovician age.

What made trilobites so successful?

In this extreme environment, symbiotic sulfur-eating bacteria grew in the gills of the trilobites, providing them with energy. This high diversity in their body types and the ability to adapt to their environment is what made trilobites successful for so long.

How did trilobites adapt to their environment?

Trilobites were able to adapt to their environment extremely well. This species had a flat head and long eye stalks, which means it likely lived in the sediment on the ocean floor. Fossils like this give scientists useful clues to what life on Earth was like millions of years ago.