How are wings of a bat different from the wings of a bird?
Bat wings consist of flaps of skin stretched between the bones of the fingers and arm. Bird wings consist of feathers extending all along the arm. Birds and bats did not inherit wings from a common ancestor with wings, but they did inherit forelimbs from a common ancestor with forelimbs.
Are bird wings and bat wings homologous?
An example of this is the wings of bats and birds. These structures are homologous in that they are in both cases modifications of the forelimb bone structure of early reptiles. But birds’ wings differ from those of bats in the number of digits and in having feathers for flight while bats have none.
Why are the wings of birds and bats considered analogous organs?
The wings of the bat have flaps of skin stretched between the bones of the fingers and the arm. Bird wings consist of feathers extending all along the arm. But both perform the same function of flying. Hence, the wings of bat and wings of bird are called analogous organs.
What is a derived condition?
Conversely, a trait that appears within the clade group (that is, is present in any subgroup within the clade but not all) is called advanced or derived. A primitive trait is the original condition of that trait in the common ancestor; advanced indicates a notable change from the original condition.
What is a shared ancestral trait?
If a characteristic is found in the ancestor of a group, it is considered a shared ancestral character because all of the organisms in the taxon or clade have that trait. The same trait can be considered one or the other depending on the particular diagram being used.
What is an example of Synapomorphy?
The concept of synapomorphy is relative to a given clade in the tree of life. For example, the presence of mammary glands is a synapomorphy for mammals in relation to tetrapods but is a symplesiomorphy for mammals in relation to one another—rodents and primates, for example.
What does Plesiomorphic mean?
plesiomorphy (ancestral trait) An evolutionary trait that is homologous within a particular group of organisms but is not unique to members of that group (compare apomorphy) and therefore cannot be used as a diagnostic or defining character for the group.
What characteristics are unique to mammals?
Characteristics of Mammals
- The presence of hair or fur.
- Sweat glands.
- Glands specialized to produce milk, known as mammary glands.
- Three middle ear bones.
- A neocortex region in the brain, which specializes in seeing and hearing.
- Specialized teeth.
- A four-chambered heart.
Do bats and birds share a common ancestor?
Homologous structures: Bat and bird wings are homologous structures, indicating that bats and birds share a common evolutionary past. Notice it is not simply a single bone, but rather a grouping of several bones arranged in a similar way.
Do bats and insects have a common ancestor?
The difference in the development, or embryogenesis, of the wings in each case is a signal that insects and bats or birds do not share a common ancestor that had a wing. The wing structures, shown in Figure 12.8 evolved independently in the two lineages. Similar traits can be either homologous or analogous.