The combination of a brick red belly and grey back seen in the American Robin, T
ID: 213561 • Letter: T
Question
The combination of a brick red belly and grey back seen in the American Robin, Turdus migratorius, are not seen in closely related species in the genus Turdus. Which term best describes these features of the American Robin relative to these other species?
a) Synapomorphy
b) Autapomorphy
c) Apomorphy
d) Symplesiomorphy
e) Shared derived character
Which of the following groups is a taxon?
a) Species, Homo sapiens
b) Order, Carnivora
c) Genus, Thylacinus
d) Both A and C are taxa
e) All of the above are taxa
Choanoflagellates greatly resemble __________, a cell type found in _______________.
a) Diatoms....Excavata
b) Amoebas....Rhizaria
c) Choanocytes....plants
d) Choanocytes.....sponges
Bryophyte hydration is reliant on
a) Xylem
b) Phloem
c) Capillary action (passive absorbance)
d) Active pumping
e) Gaseous absorbance
Explanation / Answer
1)The best term that describes the features of an american robin with its close relatives is autapomorphy.
An autapomorphy is a distinctive feature that is unique to a given taxon. In the given case, this feature is brick red belly and grey back. This feature is seen in only the american robin species and not related species in the genus.
Apomorphy is defines as a novel evolutionary trait that is unique to a particular species and all its descendants and which can be used as a defining character for a species or group in phylogenetic terms. For example possession of feathers is a feature unique to birds and is a trait that defines all the members of the Aves class.
Synapomorphy is a characteristic present in an ancestral species and shared exclusively by its evolutionary descendants.
A plesiomorphy or symplesiomorphy is an ancestral character or trait state shared by two or more taxa.
2) A taxon is defined as a taxonomic group of any rank, such as a species, family, or class. Hence in the given question all of options a, b and c are taxa.
3) Choanoflagellates greatly resemble Choanocytes , a cell type found in sponges.
4) Brypphyte hydration is reliant on Capillary action. They lack vascular tissues like xylem that can transport water and instead of roots, possess rhizoid that help in anchorage and does not participate in water and mineral uptake.