The Sand Wasps is composed from a manuscript left behind by Howard Evans upon his death in 2002, and expanded and completed by Kevin O’Neill (which is what Howard Evans intended with the manuscript). The book is a 2007 update on the natural history and behaviour of the Subfamily Bembicinae, gathering together information published since the 1966 publication The Comparative Ethology and Evolution of the Sand Wasps by Howard Evans.
Howard Ensign Evans was a world-renowned writer and entomologist, focusing on solitary wasps (that is, the wasps that aren’t eusocial). His non-technical books include a book titled Wasp Farm in which he explores the many species of wasps that live on his property at the time, and The Pleasures of Entomology, which describes several insect species and some of the people who studied them. Life on a Little-Known Planet is an excellent overview of just how fascinating insects can be if you take the time to look closer at them, and being published in 1969 contrasts the mysteries of this little-known world against the backdrop of the United States Space Program. In Howard’s opinion, laid out in the book, we would do better to explore the only planet with life because it still contains many mysteries for our curiousity. I couldn’t agree more with this sentiment.
What are Sand Wasps? Sand Wasps are Wasps of the Subfamily Bembicinae (which is a subfamily of the Family Crabronidae). Most Sand Wasps, unsurprisingly, construct their burrows in sand, or other easily movable soils, but some utilize hard clay. In all cases (except for the brood parasites), they use their mandibles and legs to construct some sort of burrow in which they will raise their young. There are many variations on the nest construction process, which the book highlights time and again. Some species close their burrows, either temporarily while they are away from the nest seeking food for their larvae or eggs inside, and/or as a final cap to their nest. These closures are presumed to be a protective measure against parasites or predators of the vulnerable young wasps within. As a further defense, some species construct false burrows beside the true nest, simple tunnels in the substrate that don’t lead to the prey a predator or parasite may be seeking. Within the true nest, there may be one or several brood cells, offshoot chambers that contain the developing young (egg, larva, or pupa) and the prey provided for the young by the parent. Here there is much variation among species: whether the mother lays the egg in each brood cell before gathering prey for the larva-to-be, or if she places her egg on top of the first prey item, or atop the mass of prey she has gathered. The type of prey, how the prey is carried, and when the prey are brought to the cell all vary according to species.
In the following Posts, we’re going to look at the five Tribes of Sand Wasps, using the book The Sand Wasps as our main guide (it is, so far as I know, the only book like this for Sand Wasps), but utilizing other sources when needed.
Evans, Howard E. and O’Neill, Kevin M. The Sand Wasps: Natural History and Behavior, 2007.
Evans, Howard E. Life on a Little-Known Planet, 1969.