Fish
In terms of biomass, the most numerous class of animals on Earth is usually considered to be arthropods, which include insects, spiders, and crustaceans. They are incredibly diverse and can be found in virtually every habitat on Earth.
Insects are not a species. Insects are are a class of invertebrates within the arthropod phylum. That is like asking if mammals are the most numerous species. Your question needs to be refined. Are you asking if insects are the most numerous class of animal? Most numerous species of living thing? Or perhaps you are thinking of a specific species such as monarch butterfly (Danausplexippus).
Birds are considered one of the most successful vertebrates due to their diversity, adaptability, and ability to inhabit nearly every ecosystem on Earth. Their unique adaptations such as flight, beaks, and diverse diets have allowed them to thrive and evolve into over 10,000 species globally.
These numbers are not accurate, as accurate number of animal species on earth has yet to be discovered. Currently it looks like less than 3% of the known species of animals on earth are vertebrates (have back bones). There are around 50 000 species of vertebrates, most of which are fish. Most animals are invertebrates, and most of those are insects.
After fish, amphibians were the next group of creatures to evolve on Earth. Amphibians are cold-blooded vertebrates that can live both on land and in water. They were the first vertebrates to colonize terrestrial habitats.
none.birds are the most numerous.
vertebrates
because they vary their habitat
fish
Pizza
planet
most invertebrates are arthropods, and 70% of animals in the world are arthropods (insects), so I'm guessing there are more invertebrates than vertebrates.
Bacteria are generally considered the most numerous organisms on Earth. They are found in virtually every environment and play crucial roles in ecosystems, from aiding in nutrient recycling to influencing human health.
fish, birds and ants
No there is also non-vertebrates which mean they don't have a spine
These numbers are not accurate, as accurate number of animal species on earth has yet to be discovered. Currently it looks like less than 3% of the known species of animals on earth are vertebrates (have back bones). There are around 50 000 species of vertebrates, most of which are fish. Most animals are invertebrates, and most of those are insects.Read more:What_percent_of_animals_on_earth_have_a_backbone
INVERTEBRATES!!