In disciplines such as macroevolution that are not amenable to experimentation, scientists usually rely on current observations to test hypotheses about historical events, assuming that "the present is the key to the past." Biogeographers, for example, used this assumption to reconstruct ancestral ranges from the distribution of extant species. Yet, under scenarios of high extinction rates, the...

Hypericaceae herb contains biologically active compounds, flavonoids (1.5–5%), naphthodianthrons, phloroglucins, tannins (10-13%), essential oil (0.1–0.33%) and other compounds. In accordance with the patent RU 2,067,452 C1, St. John's wort extract is obtained using a solvent system acetone-70% ethanol – 30% ethanol. extracted acetone. The raw materials remaining after extraction are dried 70% ...

The anatomy and ultrastructure of internodes, leaves and petals were compared in Hypericum elegans, H. inodorum, H. olympicum, H. forrestii and two genotypes of H. perforatum. Internode anatomy was variable between species with respect to the structure of the cortical and pith parenchyma, including the presence of secretory reservoirs. Also, the secondary growth was more extensive in shrubs, i....