Which the following phylogenies does not indicate the same relationship among whales and other groups? All the above show the same relationship. Each phylogeny shows a different relationship. Solution Answer: Choice D Phylogeny means the development or evolution of a particular group of organisms. In other words it is the study of evolutionary history and relationships among individuals or groups of organisms. The first thing to notice on the evogram is that hippos are the closest living relatives of whales, but they are not the ancestors of whales. In fact, none of the individual animals on the evogram is the direct ancestor of any other. That\'s why each of them gets its own branch on the family tree. The first mammals were certainly terrestrial. There is good evidence that mammals evolved from reptile-like ancestor. Therefore at some point in evolutionary history there was a transition from terrestrial environment to an aquatic lifestyle in this group of species. According to Charles Darwin whales evolved from terrestrial ancestors and re-developed the streamlined bodies as an adaptation to their aquatic lifestyle. Establishing the position of Cetacea (whales, dolphins and porpoises) within Mammalia has long been a focus of evolutionary studies. The transition from a primitively quadrupedal terrestrial ancestor to a convergently ‘fish-like’ modern mammal species involved changes in numerous character systems. Almost all anatomical systems of living cetaceans are highly modified for an aquatic lifestyle such as the ear region, skin, limbs, and cranium, in comparison to terrestrial mammals. The study of phylogenetic data of fossils has been particularly important because it is by studying extinct species that we can reconstruct the order of character acquisition that led to the origin of Cetacea. Continued discovery of fossils that capture transitional stages in cetacean evolution provides critical new data on how the stem lineage to Cetacea transformed. Incorporating new fossils into increasingly large total evidence (character congruence), we are beginning to develop a firm understanding of the evolutionary history of Cetacea and can start testing hypotheses on character transformation..

1. Which the following phylogenies does not indicate the same relationship among whales and
other groups? All the above show the same relationship. Each phylogeny shows a different
relationship.
Solution
Answer: Choice D
Phylogeny means the development or evolution of a particular group of organisms.
In other words it is the study of evolutionary history and relationships among individuals or
groups of organisms.
The first thing to notice on the evogram is that hippos are the closest living relatives of whales,
but they are not the ancestors of whales.
In fact, none of the individual animals on the evogram is the direct ancestor of any other. That's
why each of them gets its own branch on the family tree.
The first mammals were certainly terrestrial. There is good evidence that mammals evolved from
reptile-like ancestor. Therefore at some point in evolutionary history there was a transition from
terrestrial environment to an aquatic lifestyle in this group of species.
According to Charles Darwin whales evolved from terrestrial ancestors and re-developed the
streamlined bodies as an adaptation to their aquatic lifestyle.
Establishing the position of Cetacea (whales, dolphins and porpoises) within Mammalia has long
been a focus of evolutionary studies.
The transition from a primitively quadrupedal terrestrial ancestor to a convergently ‘fish-like’
modern mammal species involved changes in numerous character systems. Almost all
anatomical systems of living cetaceans are highly modified for an aquatic lifestyle such as the
ear region, skin, limbs, and cranium, in comparison to terrestrial mammals.
The study of phylogenetic data of fossils has been particularly important because it is by
studying extinct species that we can reconstruct the order of character acquisition that led to the
origin of Cetacea. Continued discovery of fossils that capture transitional stages in cetacean
evolution provides critical new data on how the stem lineage to Cetacea transformed.
Incorporating new fossils into increasingly large total evidence (character congruence), we are
beginning to develop a firm understanding of the evolutionary history of Cetacea and can start
testing hypotheses on character transformation.