Based on the analysis of the provided phylogenetic tree, here is the solution to understanding the evolutionary relationships among these animals.
Solution
This diagram illustrates a simplified evolutionary tree, showing how different animal groups are related based on shared anatomical characteristics. The diagonal line represents the evolutionary timeline, with traits appearing from bottom to top as they evolved. Each animal's position indicates the most recent common ancestor it shares with other animals on the tree.
Here is a breakdown of the evolutionary progression and the relationships:
1.
Jaws: This is the first major trait shown.
* The
Hagfish is positioned before this point, indicating it is a jawless vertebrate.
* The
Perch,
Salamander,
Lizard,
Pigeon,
Mouse, and
Chimp all have jaws, placing them in the group of jawed vertebrates (Gnathostomes).
2.
Lungs: This trait evolved after jaws.
* The
Perch (a fish) does not have lungs; it breathes with gills.
* The
Salamander,
Lizard,
Pigeon,
Mouse, and
Chimp all possess lungs, indicating they are part of the tetrapod lineage (four-limbed vertebrates), which evolved from lobe-finned fish that developed lungs for breathing air.
3.
Claws or Nails: This trait evolved after lungs.
* The
Salamander (an amphibian) does not have claws or nails.
* The
Lizard,
Pigeon,
Mouse, and
Chimp all have claws or nails, placing them in the amniote group (reptiles, birds, and mammals), which evolved from amphibians.
4.
Feathers: This is a unique trait of birds.
* Only the
Pigeon has feathers. This places it in the avian lineage, which diverged from the reptilian lineage (represented by the Lizard).
5.
Fur; Mammary Glands: These are defining characteristics of mammals.
* The
Mouse and
Chimp both have fur and mammary glands, indicating they are mammals. They share a more recent common ancestor with each other than either does with the Pigeon.
Summary of Relationships
*
Most Distantly Related: The Hagfish is the most basal organism on this tree, being jawless.
*
Fish: The Perch is a jawed fish but lacks lungs.
*
Amphibians: The Salamander is a lunged vertebrate but lacks claws/nails.
*
Reptiles & Birds: The Lizard and Pigeon are amniotes with claws/nails. The Pigeon is a bird, distinguished by its feathers.
*
Mammals: The Mouse and Chimp are mammals, distinguished by their fur and mammary glands.
In conclusion, the tree shows that the Mouse and Chimp are the most closely related species on this diagram, sharing the most recent common ancestor. The Pigeon is more distantly related to them, and the Lizard is even more distant. The Salamander, Perch, and Hagfish represent progressively earlier branches in the vertebrate evolutionary tree.
Parent Tip: Review the logic above to help your child master the concept of phylogeny worksheet.
