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30. Ocean Plant Life Feels the Heat: The ocean's vital phytoplankton are in the midst of a long decline.
29. "Ardi" Continues to Shake the Human Family Tree: This fossil female created a huge stir when discovered, but some scientists question its significance to human evolution.
28. The Incredible Shrinking Moon: Researchers find signs of a lunar lessening.
27. Egg Recall Rattles the Food Supply: After 500 million eggs are recalled, what happens next?
26. How Matter Defeated Antimatter (pictured): The Tevatron particle smasher offers hints on the universe's beneficial bias towards matter.
25. Interview with Steven Chu: Our Secretary of Energy speaks up on getting to a green-energy future.
24. Space Ship Sails on a Breeze of Sunshine: The first journey of a solar sail spacecraft is a success!
23. Comets Are Interstellar Visitors: The solar system's Oort cloud, where comets are born, may be full of immigrants from other stars.
22. Hair DNA Documents a Forgotten Migration: You can learn a lot from 4,000-year-old hair.
21. MRI Scans Track Brain Development: In six minutes, a scan can reveal if a child's brain is developing normally.