♦ 4* 



Alu llAKOLOGle T , 

 F.HAYAYr.s 



MK'HAKL n. 

 (OK 



00 



by Michael D. Coe 

 $29.95 hardcover / 224 pages / 41 illus. 



Ian Hodder 



THE LEOPARD'S TALK 



Revealing the Mysteries of QaolhovuL 



by lan Hodder 

 $34.95 hardcover / 256 pages / 150 illus. 



THE SONS OF 



CAESAR 



IMPERIAL ROME'S FIRST DYNASTY 



by Philip Matyszak 

 $31.95 hardcover / 296 pages / 80 illus. 



Thames & Hudson 



Available wherever books are sold 

 thamesandhudsonusa.com 



quickly recognized that the queen was 

 a species new to science. But the spec- 

 imen as a whole is immensely impor- 

 tant as well. It demonstrates that in- 

 vestigators seeking to understand the 

 evolution of certain behaviors — in this 

 case, trophophoresy in ants — have on- 

 ly to look closely at the life-forms en- 

 cased in amber for a golden window 

 on a former world. 



The H. protera tree, a long-extinct, 

 evergreen member of the legume 

 family, was essential to 

 the process of fossiliza- '< . — 1 



tion. The tree exuded 

 copious quantities of 

 resin to protect its frag- 

 ile inner layers when 

 they were exposed to 

 damage, perhaps after a 

 violent windstorm had 

 ripped off a branch or 

 wood-boring beetles 

 had attacked its trunk. 

 Soon after the ant 

 queens were trapped, 

 the resin began to hard- 

 en and draw moisture 

 out of the ant carcasses 

 and thus helped prevent 

 them from decompos- 

 ing. When the trees 

 died and disappeared, 

 the ants and mealybugs 

 remained entombed in 

 chunks of resin that were buried at the 

 site. As millions of years passed, the 

 resin continued to harden, becoming 

 first copal and, finally, amber. There is 

 some debate about the precise differ- 

 ence between copal and amber, but 

 most experts agree that amber must be 

 roughly the hardness of gypsum or cal- 

 cite (between two and three Mohs) and 

 that its surface should not become 

 sticky when exposed to an organic sol- 

 vent such as acetone. 



Deposits of amber fossils have been 

 found in only a handful of places around 

 the globe. After the Baltic region, the 

 Dominican Republic — half of the is- 

 land of Hispaniola — is the second 

 largest producer of amber in the 

 world. There are three main mining 



18 NATURA1 HISTO RY May 2006 



areas for Dominican amber: La Cor- 

 dillera Septentrional in the north, and 

 Byaguana and Sabana in the east. The 

 mines, according to George Poinar Jr. 

 and Roberta Poinar, in their book The 

 Amber Forest, are "small, tortuous tun- 

 nels carved into the sides of the moun- 

 tains, or sometimes pits sunk deep in- 

 to the ground" [see photograph below]. 

 Miners usually have to crawl through 

 the tunnels and chip away at rock with 

 hammers and chisels, looking for am- 

 ber. The work is hard and dangerous, 



Amber mines in the Dominican Republic are 

 the second largest source of amber in the 

 world, but passages are low and working 

 conditions are often hard and dangerous. 

 Wooden supports for the walls and ceilings 

 often fail to prevent the mines from collapsing. 



and the small mines can collapse with- 

 out warning. 



Most amber carries no traces of life. 

 But fortunately for paleobiologists, 

 many creatures did meet a sticky end. 

 Flowers, leaves, seeds, insects, spiders, 

 scorpions, and even small vertebrates 

 such as frogs and lizards have been dis- 

 covered encased in amber. Not only 

 can such fossils tell a great deal about 

 the form and structure of ancient spe- 

 cies; they can also show how lineages 

 of organisms have been distributed 

 around the world through time. For ex- 

 ample, one genus of ant, Lcptomyrmex, 

 which lives today only in eastern Aus- 

 tralia, New Caledonia, New Guinea, 

 and Seram, in Indonesia, has been dis- 

 covered inside Dominican amber, hep- 



