This bird's numbers are declining due to habitat loss largely attributed to human activity.
She attributes her brain power to good genes, healthy living and, especially, daily physical activity.
Schwab attributed the improvement to increased activity by individual investors, including the addition of more than 65,000 accounts during the quarter.
However, they do attribute a large influence to volcanic activity as he suggested.
How much change can be attributed to human activity is difficult to estimate.
The extinction of the elephant bird is attributed to human activity.
Workers at the house have reported unusual occurrences which some have attributed to paranormal activity.
Thus, they argue, only part of the temperature rise - perhaps a small part - can be attributed to human activity.
Death was attributed to unusual activity of the thymus.
The preservation of the tracks has been attributed to volcanic activity that instantly covered the paleosurface.