The scanning electron microscope has become one of the most powerful scientific visualization tools available, giving us incredible close-up views of anything from volcanic ash to snowflakes to bacteria. The microscope works by scanning a focused beam of electrons across an object. The electrons interact with the atoms at the surface of the object, revealing the texture and structure with a depth of field that makes for a great three-dimensional sense of the target. Some of the most intriguing images are those of insects and other animals. On this day in 1940, the first transmission (stationary) electron microscope, predecessor to the scanning electron microscope, was demonstrated in the United States. To celebrate the amazing contribution these microscopes have made to science, we asked scientists at the American Museum of Natural History in New York City to share some of their favorite SEM images with us. Here are the beautiful and creepy images of scorpions, wasps, sharks, bees and spiders they sent us. Solitary Bee The American Museum of Natural History houses perhaps the most complete collection of bee eggs, larvae and pupae in the world. The image above is of the larva of a ground-nesting solitary bee from Turkey. This is the last instar larval stage, which describes the times between each molt (after an insect sheds its exoskeleton in order to grow) until the insect reaches sexual maturity. Though many scientists study bees, curator Jerome Rozen is one of the few who studies solitary species and their parasites (seen on the last slide). Image: Hoplitis monstrabilis (Rozen, J.G., Jr., H. Özbek, J.S. Ascher, M.G. Rightmyer. 2009. American Museum Novitates 3645)

Scorpion Scorpions have unique sensory combs, called pectines, on their ventral sides. The combs sense textures of surfaces and detect chemical traces of their own species. Scientists also use them to distinguish males, which have larger pectines with more teeth, from females. Work on these scorpions was done by American Museum of Natural History curator Lorenzo Prendini and postdoctoral researcher Carsten Kamenz. The images above and below highlight different aspects of the pectines of various scorpion species. Above: The teeth of a sensory comb with an array of chemosensory sensilla. Above: The margin of the sensilla array on a scorpion's sensory comb. Above: The "fulcrum" on a scorpion's sensory comb. Above: The teeth of a scorpion's sensory comb. Images: Carsten Kamenz

Goblin Spider The spiders pictured here from a new species of South American goblin spiders from the family Oonopidae. It is believed that the 459 described species of goblin spiders are only about 20 percent of the total species. American Museum of Natural History curator emeritus Norm Platnick and Nadine Dupérré are studying and will soon be publishing descriptions of the new species as part of an effort to collect, image and describe the hundreds of remaining goblin spider species. The results will all be cataloged online. Above: Goblin-spider tarsal claw. Above: Male goblin-spider ventral mouthpiece. Images: Nadine Dupérré

Hover Wasp These images are of the head and antennae (left) and metasomal segments I and II of Chalogaster spatulata, a species of hover wasp from Southeast Asia recently described by American Museum of Natural History curator James Carpenter and Christopher Starr of the University of the West Indies. Images: James M. Carpenter/AMNH

Bull Shark This image is of the skin of the bull shark, an aggressive species that can tolerate fresh water and is thought to be responsible for many near-shore attacks. Shark skin is made of tiny scales known as dermal denticles that can be seen here. The scales give shark skin a very rough, sandpaper-like texture, make it very strong. The scales help streamline the shark by moving water through the grooves in the scales to reduce turbulence. Image: AMNH Microscopy and Imaging Facility manager Rebecca Rudolph.

Plant Bug These images are of Pseudosthenarus rozeni, a legume-feeding plant bug from the Namaqualand region of South Africa. This is one of more than a dozen species of Pseudosthenarus that occur in Namaqualand, and nowhere else. American Museum of Natural History curator Randall Schuh named the species for the museum's curator of bees Jerome Rozen. Images: Randall Schuh

Saxon Wasp The image above shows the mandibular teeth of the wasp Dolichovespula saxonica, described in 2006 by American Museum of Natural History curator James Carpenter and colleague Estelle Perera. The saxon wasp plays host to the social parasitic yellowjacket Dolichovespula adulterina (right). Images: James M. Carpenter/AMNH