According to an article in last month’s Smithsonian, slime molds are of the kingdom Protoctista, one of the five kingdoms of life, the others being animals, plants, fungi and bacteria.
OK- I still haven’t found an accurate (i.e. scientific article) site for bug acceleration/deceleration tolerances, but I’m working on it.
Abe- If you read my original post, its qualified with the exception that both bug and human have to be moving at the same speed. As their masses are unequal, they will also have different momentem(?- latin was nerver a strong point)and kinetic energies. However, if they impact over the same time period they will experience the same net deceleration.
Impact and impulse are essentially the same principles, namely the effect of a force over a given time period. Impulse is usually used when calculating scalar quantities, and impact is referred to in vector calculations. Impulse also has the assumption that it is the primary force during collision (i.e. all other forces are so relatively small that they may be ignored).
The slime molds, which include the cellular slime molds (Acrasiomycota) and the plasmodial slime molds (Myxomycota), have always been a headache for biologists since they combine characteristics of animals, fungi, and plants. Under the “Five Kingdom” arrangement, they are usually placed in the Protoctista (or Protista), along with unicellular forms, despite sometimes being quasi-multicellular.
However, the Five Kingdom arrangement, while much better than the traditional Plant/Animal division, does not really fit well with the prevailing taxonomic methodology of cladistics. Cladistics insists that taxonomic categories strictly conform with the branching patterns of evolutionary lineages. “Protoctista” is basically a grab-bag of unicellular forms, some of which are closer to plants, some to animals, some to fungi, and some off on some other branch entirely, and so is not an acceptable category under cladistics.
The relationships between eucaryote (non-bacterial) organisms have been difficult to work out even through genetic analysis since the major splits may have taken place more than a billion years ago. Recent work on proteins suggests that if Animalia, Plantae, and Fungi are considered as Kingdoms, then about 8 lineages of Protists would also merit that distinction, based on evolutionary branching patterns (Baldauf et al. 2000, A Kingdom-level Phylogeny of Eukaryotes Based on Combined Protein Data, Science 290: 973-977).
Among the major groups, the Animalia and Fungi appear to be more closely related to each other than either is to the Plantae. The slime molds don’t fit within any of these groups, but are closer to the Animal-Fungi lineage. Given this, if Animals, Plants, and Fungi are considered Kingdoms, then the slime molds must get their own also, the Mycetozoa.
The bacteria probably deserve multiple Kingdoms, Realms, and Empires themselves, but let’s not even get into that. Given lateral gene transfers between lineages and the postulated origin of eucaryote organelles from bacterial symbionts, even cladistics can’t deal well with some of the complexities involved.