Plants are autotrophs and sessile, while animals are heterotrophs and motile. Sessility has imposed on plants 94% hermaphroditism, 23% selfing, 3% polyploidization and 39% clonality, in comparison to < 5% herma-phroditism, < 1% selfing and 2% clonality in motile animals. Whereas plants consist of 374,000 species but 1,664 variety/species, animals comprise 1,543,196 species and 210 variety/species. Hence, plants have undergone variety diversity, while animals have species diversity. In animals and plants, the species ratio is reduced from 4.1 animals : 1.0 plant to 1.4 for pollinating animals : 1.0 pollinated plants. In pollination, animals are benefited dietarily but plants are cross pollinated, generating new gene combinations the raw material for evolution and speciation. For the reduced species diversity in plants, reasons are traced to 90% hermaphroditism, ~ 23% selfing and 39% clonality. Clonality decreases from 100% in 6-7 tissue typed sponges and 3 tissue typed algae drastically to 0.7% in 60 tissue typed worms but gradually to ~ 23% in 60 tissued typed angiosperms. About 12-15, 5-8 and 77-80% of all animal and plant species are distributed in marine, freshwater and terrestrial habitats, respectively. Animals have conserved the right sequence of gametogenesis but plants have gone through a wrong sequence prior to settling with right one albeit with double fertilization in angiosperms. Both animals and plants are 80% male heterogametics. Only 0.5% of them can afford semelparity. While 20 and 57% angiosperms are perennial trees and herbs, annual herbs make up 23% only. In all of them, 85, > 19 and < 1% are pollinated by fast flying animals, wind and water, respectively. Increasing pollen load enhances fruit- and seed-set. In contrast to animals, the life cycle of plants is direct but complicated. Unlike animals, plants have greatly contributed to weathering of rocks and the atmospheric gas composition during the geological past. From dormant spores and seeds of plants, life can be restored after thousands of years.
Plants are autotrophs and sessile, while animals are heterotrophs and motile. Sessility has imposed on plants 94% hermaphroditism, 23% selfing, 3% polyploidization and 39% clonality, in comparison to < 5% herma-phroditism, < 1% selfing and 2% clonality in motile animals.
1. General Introduction Part A: Environmental Factors
2. Photosynthesis
and Chemosynthesis
3. Phototrophic Heterotrophy
4. Spatial Distribution Part
B: Life History Traits B1: Sexuality
5. Monoecy: Reproductive Systems
6.
Dioecy and Sex Ratio
7. Polyploids Hybrids Grafts
8. Parthenogenesis
Apomixis
9. Clonals and Stem Cells Part C: Gametogenesis and Fertilization
10. Oogenesis and Spermatogenesis
11. Heterogamety Sex Genes
12. Annuals
Herbs Semelp
13. Pollination and Coevolution
14. Self- and
Cross-Fertilization
15. Spores Seeds Dispersal Part D: Germination and
Development
16. Germination and Recruitment
17. Brooders and Vivipares
18.
Sex Determination
19. Hormones and Differentiation Part E: Past, Present and
Future
20. Past: Weathering and Oxygenation
21. Present: Conservation and
Dormancy
22. Future: Climate Change
23. References
T.J. Pandian, recipient of the S.S. Bhatnagar Prize, the highest Indian award for scientists, one of the ten National Professorships, has served as editor/member of editorial boards of many international journals. His books on Animal Energetics identify him as a prolific but precise writer. His five volumes on Sexuality, Sex Determination and Differentiation in Fishes, published by CRC Press, are ranked with five stars. He has authored a multi-volume series on Reproduction and Development of Aquatic Invertebrates, of which the volumes on Crustacea, Mollusca, Echinodermata and Prochordata, Annelida, Platyhelminthes and Minor Phyla have been published. The CRC Press has recently published his new book series on Evolution and Speciation in Animals. The second volume on Evolution and Speciation in Plants is presented here.
