Where did Astraspis live list four states where they have been found?

Where did Astraspis live list four states where they have been found?

They are represented by a single genus, Astraspis, including possibly two species, A. desiderata and A. splendens but their remains are fairly abundant in Ordovician sandstones of the USA (Colorado, Arizona, Oklahoma, Wyoming) and Canada (Quebec).

Do Agnatha lay eggs?

After migrating upstream the males build a rock nest-like structure, the females lay the eggs then the males release their sperm over the nest. Lampreys die shortly after spawning.

What are the characteristics of jawless fish?

The jawless fish include the lampreys and the hagfish. Jaws, fins, and stomachs are absent in the jawless fish. Features of the jawless fish include a notochord, paired gill pouches, a pineal eye, and a two-chambered heart.

Did dinosaurs evolve fish?

Paleontologists have discovered fossilized remains of the world’s oldest bony fish, which swam the Devonian seas 400 million years ago. As the earliest known bony fish, “Ligulalepis” is closely related to our own ancestors.

What animals have no jaws?

Cyclostomes are a monophyletic group of eel-shaped animals that include modern hagfish and lampreys. Members of both groups have cartilaginous skulls, qualifying them as true crown-group vertebrates, but lack jaws. In fact, they are the only two groups of extant vertebrates that lack jaws.

What are 2 examples of jawless fish?

There are two categories of jawless fish: hagfish and lampreys.

What is Agnatha give example?

Pteraspidomorphi
Haikouichthys
Jawless fish/Lower classifications

Are fish older than dinosaurs?

Since the extinction event that wiped out the dinosaurs 66 million years ago, fish have evolved and diversified, leading to the wide variety of fish species we see today. Sixty-six million years ago, it was a tough time to be a dinosaur (since they were, you know, all dying), but it was a great time to be a fish.

What fish is older than dinosaurs?

coelacanths
Bright blue, older than dinosaurs and weighing as much as an average-sized man, coelacanths are the most endangered fish in South Africa and among the rarest in the world.

Which is the second trophic level of the food chain?

The second trophic level consists of organisms that eat the producers. These are called primary consumer s, or herbivore s. Deer, turtles, and many types of birds are herbivores. Secondary consumers eat the herbivores. Tertiary consumer s eat the secondary consumers.

Which is the first position on the food chain?

one of three positions on the food chain: autotrophs (first), herbivores (second), and carnivores and omnivores (third). an opening in the Earth’s crust, through which lava, ash, and gases erupt, and also the cone built by eruptions.

What makes up the food chain in a pond?

1 The Food Chain in a Pond Sunlight provides energy for plants to grow. 2 Pond Plants Algae Duckweed Elodea Cattails Water lily

How are food chains related to the food cycle?

all related food chains in an ecosystem. Also called a food cycle. (singular: fungus) organisms that survive by decomposing and absorbing nutrients in organic material such as soil or dead organisms. “simple sugar” chemical produced by many plants during photosynthesis.