What can animals with backbones do that animals without back bones cannot do?

Answer 1

They are not, actually. The reason for that because animals with external skeletons (exoskeletons) have more surface area for their muscles to bind onto, giving them more leverage and strength. Animals with internal skeletons have far less surface area for the muscles to bind onto, thus limiting their strength. The average healthy human can lift their own body weight. Something like, oh say your average rhino beetle can lift up to 850 times their own body weight! Huge difference, and it's all because of surface area. The downside to having an exo skeleton, however, is that you have a limit on how large you can grow. The bigger you get with an exoskeleton, the more exponentially you'll feel the force of gravity on you until you simply can't hold yourself up anymore.

There are animals that have no backbone, but also lack an exoskeleton. These animals tend to be squishy, but many of them can actually regenerate body parts. A perk, if you ask me.

Answer 2

The first animals that developed were unicelluar. The diverse population of single celled plants and animals in the ocean have many niches to fill that cannot be occupied by more complex animals. Simple multicelluar animals evolved to further capitalize on this same environment. As complexity increased in the ocean environment there is still a limited need for a nervous system for many even more complex animals (jelly fish and other coelenterates). The chordates include many species with a notochord but still no bones. For many of these animals their stucture is ideally suited to the

environment, with no "pressure" for the type of change that would require a backbone.

The primary reason for bones in an aquatic environment is probably locomotion.

Still, this level of complexity requires more energy to sustain and adaptations that

allow animals to move does not require a backbone in many instances.

From a simple developmental standpoint animals with no skeletal structures are now much more numerous than those with bones.

Also, from the standpoint of biomass, there are many many more simple animals that can be sustained in an environment than more complex one. They have been around longer, can and have filled more niches than animals with backbones, and can also reproduce more rapidly, using less energy than a large, more complex animal with a

skeletal system.

Answer 3

Sometimes, the difference is that animals without back bones cannot stand upright, like a human. However, some animals without backbones can rise upright, some snakes do that.

Answer 4

Yes, 98% of animals are invertebrates (they do not have backbones).