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Young low-mass galaxies with extreme emission-line properties are ubiquitous at high redshift. However, a detailed characterisation of their physical properties, key for understanding cosmic reionisation and the early growth of galaxies, will be only possible with JWST and ELT observations. Rare lower-z analogues of these primeval galaxies provide us ideal laboratories to study in larger detail the complex physical mechanisms taking place in these extreme systems. In this talk, I will review key results from these high-z analogues, with an emphasis on lessons learned from deep spectroscopic observations of green pea galaxies at z ⩽ 0.3. New recent results based on high-dispersion Echelle and IFU spectroscopy of green peas will be presented. They illustrate current advantages and limitations of the chemodynamical analysis for a simultaneous study of the ionised gas kinematics, chemical enrichment and the escape of ionising photons in compact low-mass starbursts.

The escape fraction of Lyman continuum (LyC) radiation from galaxies remains one of the primary uncertainties in studies of reionization. However, few LyC-emitting galaxies are known. The recently identified, low-redshift “Green Pea” (GP) galaxies exhibit a number of similarities with high-redshift galaxies, and their optical emission lines suggest they may be some of the elusive LyC emitters. Recent HST COS and ACS observations of four GPs suggest further evidence for LyC escape and give new insights into the origins of Lyα and low-ionization UV lines in high-redshift galaxies. The Lyα emission and low-ionization emission and absorption lines provide a coherent physical picture of the neutral gas distribution in the GPs and may identify LyC emitters at high redshift. The rare, low-redshift GPs hint at possible factors that may enable LyC and Lyα escape from high-redshift galaxies.

1. The absorption of zinc in humans from composite meals, was determined by extrinsic labelling of the meals with65Zn and measurement of the whole-body retention of the radioisotope.2. Low-Zn (mean 25 μmol) chicken meals with 150 g white bread or 225 g potatoes, carrots, turnips, cabbage or green peas were studied. The effect of a beet-pulp-fibre preparation used as a breakfast cereal, in bread and as a meat extender on Zn absorption was also studied.3. The mean percentage absorption from the chicken meals with white bread, carrots and cabbage was significantly different from the meals with potatoes, turnips and green peas. When the amount of Zn in the meals was taken into account a slightly higher absorption was observed from the white-bread meal compared with the meals with potatoes and cabbage, while no differences were seen between the vegetable meals.4. The beet-pulp-fibre preparation did not affect the extent of Zn absorption when used as a meat extender. The absorption of Zn was higher when the beet fibre was included in bread than when used as muesli.5. The results obtained suggest that, besides the low-Zn content in vegetables, a large intake of vegetables or a pure-vegetable-fibre preparation has no significant effect on Zn availability from animal-protein-based meals.

1. An account is given of Marsh Spot in the seeds of the green pea (Pisum sativum L.); its economic importance and its effect on the plant, including the germination of the seed, are discussed.2. Hypotheses advanced by seedsmen and growers to account for the presence of Marsh Spot are discussed.3. The soils of 165 fields upon which green peas were grown under contract for seed in east Kent during 1933 and 1934, were surveyed in detail and are classified under the American system. A brief description of each is given.4. The occurrence of Marsh Spot is correlated with the presence of a water table in the soil. A high percentage of Marsh Spot was encountered only in crops grown on fields with a water table within 52 in. of the surface. Thus, in the presence of a water table, the intensity of Marsh Spot reached a maximum of 100 per cent. of the seeds of a sample affected, whereas in the absence of a water table the maximum was only 3 per cent.

SUMMARYYield and growth analysis has been carried out on vining peas (variety Dark Skinned Perfection) sown at 43, 97 and 172 seeds/m2 at a rectangularity of 1:1. No difference wasobtained in the yield of green peas (at tenderometer reading 110) over this fourfolddifferencein sowing density.At a high seed rate (172/m2) a high peak leaf area (8·3) was attained 1 week afterthe start of flowering but declined rapidly. The peak number of flowers and pods reached 1002/m2 at this density, but there was a greater wastage (34 %) by abscission than inthe lower seed rates which resulted in a similar number of pods/unit area being present at the time of vining for all densities.In contrast, peas sown at low density (43/m2) resulted in a lower peak leaf area (4·3) but this occurred during the stage of pod fill; net-assimilation rate was somewhat higher also. Thus the yield of green peas may depend less on the ability of the plant stand to provide reproductive nodes than on its ability to produce photosynthate during the post-flowering period.