Phylogeny describes a species:
(a) evolutionary history
(b) geographic distribution
(c) morphological similarities with other species
(d) reproductive compatabilities with other species

Options

A. evolutionary history
B. geographic distribution
C. morphological similarities with other species
D. reproductive compatabilities with other species

Explanation

To solve the question regarding what phylogeny describes about a species, we can break it down step-by-step:

### Step 1: Understand the term "phylogeny"
Phylogeny refers to the evolutionary history and development of a species. It encompasses how a species has evolved over time and its relationships with other species.

### Step 2: Analyze the options
- **(a) evolutionary history**: This directly aligns with the definition of phylogeny, as it describes how a species has developed and evolved.
- **(b) geographic distribution**: This refers to where a species is found geographically, which is not the primary focus of phylogeny.
- **(c) morphological similarities with other species**: While morphology can be a part of phylogenetic studies, phylogeny itself is broader and focuses more on evolutionary relationships rather than just physical similarities.
- **(d) reproductive compatibilities with other species**: This relates to how species can interbreed, which is not the main aspect of phylogeny.

### Step 3: Identify the correct answer
Given the definitions and analyses of the options, the correct answer is:
**(a) evolutionary history**. This option best describes what phylogeny entails.

### Summary of the Solution
Phylogeny describes a species' evolutionary history, making option (a) the correct choice.

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