Which one of the following animals it's most likely to be a keystone species based on the food web provided mouse grasshopper frog deer

The frog is most likely to be a keystone species based on the food web provided.

Based on the given options, the most likely keystone species is the frog. Keystone species are species that have a disproportionate impact on their ecosystem compared to their abundance. In this case, if the frog were removed from the food web, it could cause a significant disruption to the balance of other species. The frog likely preys on both the grasshoppers and the mice, regulating their populations, and also serves as a food source for other predators like the deer.

To determine which animal is most likely to be a keystone species based on the given food web of mouse, grasshopper, frog, and deer, we need to understand the concept of a keystone species and its role in an ecosystem.

A keystone species is an organism that has a crucial impact on its surrounding environment and community, with a disproportionately large influence on the ecosystem's biodiversity and structure. If a keystone species is removed, it can cause significant disruptions to the entire ecosystem.

To identify the keystone species, we can look for an animal that has a considerable influence on the other species in the food web. In this case, let's analyze the relationships between the animals given:

1. Mouse: Typically, mice are not keystone species as they are not known to have a significant impact on other species in their ecosystem.

2. Grasshopper: While grasshoppers play an essential role in the food web as herbivores, they are not typically considered keystone species. Their removal would affect the availability of food for other animals but may not cause a widespread disruption.

3. Frog: Frogs are predators that feed on insects, including grasshoppers. While frogs do have some influence on the grasshopper population, their removal would not have a substantial impact on the entire food web or other species.

4. Deer: Among the given options, deer are more likely to be a keystone species. Deer are herbivores and have a profound effect on the community structure and plant diversity in their habitat. Their browsing behavior can shape vegetation composition and distribution, indirectly influencing other species depending on those plants.

Therefore, based on the information provided, the most likely keystone species among the options given is the deer. However, it's important to note that a thorough analysis of the specific ecosystem and its interactions would be necessary to make a definitive conclusion.