Ancient bee, trapped in 

 amber, bears a load 

 of orchid pollen. 



#5jr 



One for the Record 



When the poet William Cullen Bryant wrote that the "loveliest of 

 lovely things are they on Earth that soonest pass away," he could 

 easily have been describing orchids. Although experts agree 

 that they've brightened the planet for millions of years and now 

 number well over 20,000 species, the ephemeral plants have 

 never appeared in the fossil record . . . until now. 



An ancient stingless bee was found trapped in a piece of 

 amber 15 to 20 million years old, with a precious few packets of 

 orchid pollen clamped to its back. That singular plant-and- 

 pollinator duo enabled Santiago R. Ramirez, a graduate student 

 at Harvard University, and several colleagues to make previously 

 impossible determinations about orchid evolution. 



On the basis of the shape and packaging of the pollen grains, 

 Ramirez positioned the orchid — Meliorchis caribea, a species 

 new to science — on a phylogenetic tree. He then calibrated 

 the tree with existing molecular data from the rest of the orchid 

 family. Orchids, he found, started diversifying about 65.5 million 

 years ago, from a common ancestor that probably arose some 

 80 million years ago. That means the original lovelies may have 

 bloomed alongside the dinosaurs — much earlier than most 



orchid biologists had thought. (Nature) 



-Erin Espelie 



Tell Tail 



Coping with rattlesnakes is a fact of life for California ground squirrels. 

 Fortunately, adult squirrels are immune to the snake's venom. To pro- 

 tect their susceptible pups, when a rattler comes near they sound an 

 alarm, then fling pebbles and sand at the predator. Now, a team at the 

 University of California, Davis has discovered a previously unknown 

 means of communication in the squirrels' defensive arsenal: they warm 

 up their tails to tell the heat-sensitive vipers they mean business. 



Biologists have long observed squirrels flagging their tails in the 

 air when threatened by rattlesnakes or gopher snakes. By pointing an 

 infrared camera at the squirrels, Aaron S. Rundus and his team discov- 

 ered that the squirrels' tails were several degrees hotter than normal 

 while waving at rattlesnakes, which have specialized heat detectors, 

 but not while waving at gopher snakes, which lack such detectors. 

 The thermal signal, the authors posit, is meant for rattlesnakes. 



To test whether rattlesnakes actually pay attention to the warning, 

 Rundus's team designed a robotic squirrel with a temperature- 

 controlled tail. Indeed, when the tail warmed up, rattlesnakes slith- 

 ered away, apparently discouraged to learn that the "squirrel" had 

 spotted them, foiling a surprise attack. The squirrels' use of heat to 

 get their message across is a first in the animal kingdom. (PNAS) 



— Brendan Borrell 



Nothing Much 



News flash: astronomers think they've 

 discovered a whole lot of nothing. In the 

 constellation Eridanus, near Orion, some 10 

 billion light-years from Earth, there appears 

 to be a vast expanse of empty space, com- 

 pletely devoid of matter — no stars, no plan- 

 ets, no black holes, no gases, not even any 

 dark matter. It's almost a billion light-years 

 across, more than sixty times larger than any 

 previously known cosmic void. 



The void's discoverers — Lawrence Rudnick 

 of the University of Minnesota, his collabora- 

 tor Liliya R. Williams, and his graduate student 

 Shea Brown — already knew the region was un- 

 usual because cosmic microwave background 

 radiation (ubiquitous faint radio waves left 

 over from the big bang) appears much weaker 



there than elsewhere in the cosmos. 

 Then the team's analysis of data from 

 the Very Large Array radio telescope in 

 New Mexico eliminated the possibility that 

 the region's microwave signal was being 

 obscured by radio waves from nearby gal- 

 axies: there are just too few "radio galax- 

 ies" in the vicinity to do the job. 



The remaining possibility was 

 empty space, which could also 

 weaken the signal — thanks to the 

 effect of omnipresent dark energy 

 Rudnick's calculation of the void's 

 colossal size is based on the ap- 

 parent weakness of the radia- 

 tion. (Astrophysical Journal) 



* 



-S.R. 



Constellation 

 Eridanus, The River 



