Representative organism Type of symmetry (Radial, Bilateral, or None) Type of skeleton (ENdoskeleton, EXoskeleton, or None) Type of appendages (Jointed, Not Jointed, or Absent) Segmentation (Present or Absent) Sponges
Cnidarians
Roundworms
Annelids
Mollusks
Arthropods
Echinoderms
Vertebrates

Sponge; Radial Symmetry; Endoskeleton; Absent Appendages; Absent Segmentation

Cnidarians; Radial Symmetry; No Skeleton; Non-Jointed Appendages; Absent Segmentation

Roundworms; Radial Symmetry; No skeleton; Absent Appendages; Absent Segmentation

Annelids; Radial Symmetry; No skeleton; Absent Appendages; Present Segmentation

Mollusks; Bilateral Symmetry; Exoskeleton; Non-Jointed Appendages; Absent Segmentation

Arthropods; Bilateral Symmetry; Exoskeleton; Jointed Appendages; Present Segmentation

Echinoderms; Bilateral Symmetry; Endoskeleton; Non-Jointed Appendages; Absent Segmentation

Vertebrates; Bilateral Symmetry; Endoskeleton; Jointed Appendages; Absent Segmentation

hi~~

i would say that hybridization occurs frequently in nature, because there are many types of hybrids that have occurred naturally, such as the mule (male donkey + female horse)