Final answer:
After the extinction of the Tennessee riffleshell, the ecosystem likely experienced disruptions in its food chain, increased presence of invasive species, and possibly decreased biodiversity and habitat functionality.
Step-by-step explanation:
The extinction of the Tennessee riffleshell, a species of freshwater mussel, would most likely have led to several ecological consequences. When a species goes extinct, it can disrupt the food chain, potentially causing ripple effects throughout the ecosystem. Aquatic animals that might have relied on the Tennessee riffleshell as a food source or as part of their habitat may have struggled or needed to adapt to its loss. Moreover, the absence of the Tennessee riffleshell could have opened up opportunities for invasive species to establish themselves, further altering the ecological landscape.
Extinctions in aquatic ecosystems can also be caused by factors such as habitat loss, overexploitation, and pollution. In the Great Lakes, for instance, the introduction of invasive species like zebra mussels has caused significant declines in native species. Similarly, the extinction of the Tennessee riffleshell may have led to decreased biodiversity and compromised the functioning of its native habitat.