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Indeterminate vegetative growth
Indeterminate growth allows plants to effectively be immortal, because as they grow, they are generating new tissue every year. Many plants exhibit indeterminate proliferating organs (shoots), by means of axillary and apical meristems, which are capable of continued vegetative growth and the production of organs for sexual reproduction. Blackberries are an example of this reproduction.

For example, wild strawberries are often established by sexually produced seeds and then spread by runners. This strategy is used by invasive plants that colonize open sites. Asexual propagation is widely used in horticulture and agriculture. Many varieties of ornamental plants can only be propagated vegetatively to retain their characteristics. While we have this example of asexual reproduction, vegetative growth is also a version of this.

Evolution of early land plants
The evolution of land plants represents a foundational phase in plant evolution. The life cycle plants is characterized by gametophyte and sporophyte stages. Gametophytes, the haploid plant body, produce shoot like structures with an indeterminate apical cell responsible for repetitive organ production. Most sporophytes exhibit indeterminate proliferating organs (shoots), by means of apical meristematic activity, bearing multiple sporangia. Plants made the transition from aquatic to terrestrial environments.

The first land plants
The earliest land plants are thought to have been charophyte algae that were capable of surviving out of water. An important characteristic of these plants was their ability to extend their thallus across the soil surface by indeterminate growth, which facilitated the spread and diversification of plants across the landscape. This continued for millions of years as adaptations enabled new plant lineages to radiate into drier habitats as their dependence on water for survival and reproduction incrementally decreased. As plants spread and diversified, they created the foundation for terrestrial ecosystems that ultimately supported diverse consumer and decomposer assemblages.

Asexual reproduction
A common sexual reproduction process seen in plants is asexual reproduction. Weeds are an example of this reproduction, like dandelions and blackberries. These weeds are able to have a wide geographical range because they are apomictic. This is the asexual formation of a seed from the maternal tissues of the ovule, avoiding the processes of meiosis and fertilization, leading to embryo development. Many other plants spread through a combination of sexual and asexual reproduction.

Apomixis
Agamospermy  on the other hand is asexual by the fact a plant is reproducing by asexual seeds, or apomictic seeds. The plant, which in the case of agamospermy would contain two complete sets of chromosomes. Eventually it will undergo sporophyte embryogenesis. This is when the cells grow into a mature embryo which is later categorized into two fields: gametophytic apomixis and sporophytic apomixis.

Gametophytic apomixis represents all types of apomixis where the maternal seed embryo develops from the egg cell of a well-developed embryo sac, without fertilization. Gametophytic apomicts are then again divided apospory and diplospory. Apospory is the development of 2n gametophytes, without meiosis and spores, from vegetative, or nonreproductive, cells of the sporophyte. Diplospory is a gametophytic apomixis in which the megagametophyte arises from a cell of the archesporium (the cell or group of cells from which spore mother cells develop).

Sporophytic apomixis, also referred to as adventitious embryony, is a process in which the embryo arises directly from the nucellus (the central part of an ovule, containing the embryo sac) or the integument of the ovule. The embryo development is initiated as a bud-like structure through mitotic division of the cell nucleus.

Apomixis produces seed progeny that are exact replicas of the mother plant. The major advantage of apomixis over sexual reproduction is the possibility to select individuals with desirable gene combinations and to propagate them as clones. This would overall simplify the process for large scale seed production.

There are a few hypotheses for why this happens as one travels further into the northern latitudes. For starters the northern plants have been studied for agamospermy more so than southern latitude plants which means it is just speculation. The lack of need for pollination may provide an advantage in areas with cold summers. Agomospermous hybrids are more vigorous which is an advantage. Both polyploidy and hybridization are connected to agamospermy which means its an accidental correlation between plants of the northern hemisphere. And also agamosperms can establish from single seeds so it's more efficient for colonization in colder regions. The trade off for these characteristics could very well be found in the reproductive organs of the plants themselves. As the plants evolved into into this, they could have gotten rid of, or transformed their sex organs into a reduced genetic form to make this possible.