Question

. Scientists have measured the number of
species in different aquatic ecosystems.
Where would you expect there to be
less biodiversity?
a. The Great Barrier Reef in the
ocean off of Australia
b. A small, human-made, catfish
lake at the local park
c. The Nile River in the tropical
portion of Africa
d. Lake Michigan, the largest Great
Lake
2. Which of the following has the biggest
impact on biodiversity in ecosystems?
a. Habitat loss
b. Climate change
c. Invasive species
d. Overexploiting

Answer 1

1. b. A small, human-made, catfish lake at the local park.
- Small, artificial ponds are low in habitat complexity, area, and niche diversity, are often managed/stocked (few species), and suffer edge effects and pollution — all factors that reduce species richness compared with large, natural ecosystems like coral reefs, tropical rivers, or large lakes.

2. a. Habitat loss.
- Globally, loss and fragmentation of habitat (conversion to agriculture/urban areas, deforestation, wetland drainage, etc.) is the single largest driver of biodiversity decline because it removes or fragments the space species need to survive and reproduce. Other factors (climate change, invasive species, overexploitation) are important too, but habitat loss is the primary current threat.