Biogeography

Biogeography is the study of the distribution of animals.


Using Song Meters to Count Frog Populations

California Red-legged Frog Photo Credit: G. Fellers, U.S. Geological SurveyCalifornia Red-legged Frog Photo Credit: G. Fellers, U.S. Geological Survey

Conservationists are using cameras, acoustic sensors, and other audio recording devices to isolate the sounds of the red-legged frog among the cacophony of other nocturnal amphibians in the Watsonville Slough in Santa Cruz County.

How Many Trees are There in the World?

Map of the world's forests. Source: Crowther et al, 2015.Map of the world's forests. Source: Crowther et al, 2015.

According to the latest research, the total number of trees in the world is 3.041 trillion (that’s 3,041,000,000,000).  The revised number is almost eight times more than the previous estimate of 400 billion trees.  Previous estimates were based solely on satellite imagery, whereas the new estimates used calculations based on how much of […]

Map of the World Without Humans

The natural diversity of large mammals is shown as it would appear without the impact of modern man (Homo sapiens). The figure shows the variation in the number of large mammals (45 kg or larger) that would have occurred per 100 x 100 kilometer grid cell. The numbers on the scale indicate the number of species. Credit: Soren FaurbyThe natural diversity of large mammals is shown as it would appear without the impact of modern man (Homo sapiens). The figure shows the variation in the number of large mammals (45 kg or larger) that would have occurred per 100 x 100 kilometer grid cell. The numbers on the scale indicate the number of species. Credit: Soren Faurby

In a world without humans, elk and buffalo would roam the Great Plains and elephants might still trumpet across Europe.

Gap Analysis

GAP ecological gap analysis map. Map: USGS.GAP ecological gap analysis map. Map: USGS.

Gap analysis is a way of mapping different areas of biodiversity for researchers and conservationists to detect potentially endangered species as well as other political, ecological, and demographic features of the same region. Gap analysis is incredibly helpful for discovering the effectiveness of current conservation efforts as well as determining […]

Island Biogeography

Theory of Island Biogeography illustrated in a graph. Graph: Wikipedia.Theory of Island Biogeography illustrated in a graph. Graph: Wikipedia.

The biogeography of islands is a fascinating topic that extends to more than just island locations. The ‘island’ part of ‘island biogeography’ can refer to actual islands as well as isolated areas such as mountaintops, valleys, and other secluded spaces of unique biodiversity. These areas, surrounded by unsuitable habitat, often […]