Which statement is true about endothermy in mammals and birds? a. They both inherited this trait from a common ancestor. b. Birds are more closely related to mammals than to reptiles. c. Endothermy arose independently in these two lineages. d. Birds are reptiles and all reptiles are ectothermic.

Verified step by step guidance

1. Step 1: Understand the question. The question is asking which statement is true about endothermy in mammals and birds. Endothermy is the ability of an organism to maintain its body temperature within certain boundaries, even when the surrounding temperature is very different.
2. Step 2: Analyze each statement. Statement a suggests that mammals and birds inherited endothermy from a common ancestor. Statement b suggests that birds are more closely related to mammals than to reptiles. Statement c suggests that endothermy arose independently in mammals and birds. Statement d suggests that birds are reptiles and all reptiles are ectothermic.
3. Step 3: Evaluate each statement. Statement a is not necessarily true because while mammals and birds share a common ancestor, it's not confirmed that this ancestor was endothermic. Statement b is incorrect because birds are more closely related to reptiles than to mammals. Statement d is incorrect because not all reptiles are ectothermic and birds are not considered reptiles.
4. Step 4: Choose the correct statement. Based on the analysis, the correct statement is c. Endothermy arose independently in mammals and birds. This is supported by the fact that these two groups are not closely related, yet both exhibit endothermy.
5. Step 5: Confirm the answer. The correct answer is c. Endothermy arose independently in these two lineages.

Key Concepts

Endothermy

Endothermy refers to the physiological ability of an organism to maintain a stable internal body temperature regardless of external environmental conditions. This trait is characteristic of mammals and birds, allowing them to remain active in a variety of habitats and climates. Endothermic animals generate heat through metabolic processes, which is crucial for their survival and activity levels.

Common Ancestry

Common ancestry is a fundamental concept in evolutionary biology that suggests different species share a common ancestor from which they have diverged over time. In the context of endothermy, understanding whether mammals and birds inherited this trait from a shared ancestor or developed it independently is essential for interpreting evolutionary relationships among these groups.

Phylogenetic Relationships

Phylogenetic relationships describe the evolutionary connections between different species based on their evolutionary history and genetic data. In this context, determining whether birds are more closely related to mammals or reptiles involves analyzing their evolutionary lineage, which can reveal insights into the development of traits like endothermy and the classification of these animals within the broader tree of life.