An edible seed is a seed that is suitable for human or animal consumption. Of the six major plant parts, seeds are the dominant source of human calories and protein. A wide variety of plant species provide edible seeds; most are angiosperms, while a few are gymnosperms. As a global food source, the most important edible seeds by weight are cereals, followed by legumes, nuts, then spices. Cereals (grain crops) and legumes (pulses) correspond with the botanical families Poaceae and Fabaceae, respectively, while nuts, pseudocereals, and other seeds form polyphylic groups based on their culinary roles. Grains (cereals and millets) Grains are the edible seed of a plants in the grass family Poaceae. Grains come in two varieties, the larger grains produced by drought-sensitive crops are called cereals, and the smaller drought-resistant varieties are millets. Grains can be consumed in a variety of ways, all of which require husking and cooking, including whole, rolled, puffed, or ground into flour. Many cereals are present or past staple foods, providing a large fraction of the calories in the places in which they are eaten. Today, cereals provide almost half of all calories consumed in the world. Other grasses with edible seeds include: Astrebla pectinata – barley Mitchell grass Brachiaria piligera – wattle signalgrass Eragrostis eriopoda – woollybutt grass Panicum species, such as native millet (Panicum decompositum) and hairy panic (P. effusum) Themeda triandra – kangaroo grass Yakirra australiensis – bunch panic Pseudocereals A pseudocereal, or pseudocereal grain, is the edible seed of a pseudocereal, one of a polyphyletic group of plants that produce seeds that resemble those of cereals. Pseudocereals are used in many of the same ways as cereals. Legumes A legume, or pulse, is the edible seed of a legume, a plant in the family Fabaceae. Legumes can be divided into grams, which do not split, and dals, which split. Although some beans can be consumed raw, some need to be heated before consumption. In certain cultures, beans that need heating are initially prepared as a seed cake. Beans that need heating include: Acacia species (wattleseed), such as mulga (Acacia aneura), Halls Creek wattle (A. cowleana), southern ironwood (A. estrophiolata), umbrella bush (A. ligulata), Murray's wattle (A. murrayana), curara (A. tetragonophylla), witchetty bush (A. kempeana), wiry wattle (A. coriacea), mallee golden wattle (A. notabilis), ranji bush (A. pyrifolia), bardi bush (A. victoriae), coastal wattle (A. sophorae), shoestring acacia (A. stenophylla),