what is symbotic plant
Answers
Symbiosis works on many different scales, as is clearly illustrated by the relationship between alder (Alnus glutinosa) and a bacterium (Frankia alni). In this case, Frankia lives within special nodules on the roots of the alder (another example of endosymbiosis), and absorbs nitrogen from the atmosphere, 'fixing' it in the soil. This benefits the alder, which via photosynthesis provides the bacteria with sugars. The soil becomes enriched as a result of this process, and alder has been used in ecological restoration projects in various parts of the world, to restore depleted soils.
Ruminants are hooved mammals that digest their food in two stages. Examples in the Caledonian Forest include red deer (Cervus elaphus), roe deer (Capreolus capreolus) and the now-extinct aurochs (Bos primigenius). Ruminants have a complex digestive system, and depend on symbiosis for their survival. After their food is regurgitated to be chewed as 'cud', it then enters one of four stomach chambers where bacteria break down the otherwise indigestible cellulose in the plant material. While these bacteria use nearly all of the glucose from the cellulose, they produce volatile fatty acids, providing their host mammal with energy.
Pollination
Many of these relationships are difficult to see, but pollination is a form of symbiosis that can be observed quite easily. There are many flowering plants in the Caledonian Forest. Flowers act as powerful advertisements to insects, offering energy-rich nectar. The visiting insect, having fed upon the sugary liquid, then goes on to carry pollen to fertilise other flowers, benefiting the overall population of that particular plant species.
Some insects are fairly specific in their choice of plant. Certain bee species have a longer 'tongue' than others, and this affects their choice of flower. The three banded white-tail bumblebee (Bombus hortorum) (a species found in Glen Affric) for example, chooses deeper flowers such as foxglove (Digitalis purpurea). The shorter-tongued bees can only drink nectar from flowers that are not as deep, such as raspberry (Rubus idaeus) and goat willow (Salix caprea).
Butterflies are also very visible in their role as pollinators. For example, the pearl-bordered fritillary (Boloria euphrosyne) can be found in open deciduous woodland where it visits spring flowers such as bugle (Ajuga reptans), birds-foot trefoil (Lotus corniculatus) or dandelion (Taraxacum officinale), for their nectar.
Pollination probably evolved in response to early insects eating the pollen itself. Plants that offered organic matter (ie nectar) as an alternative to pollen for insects to feed on would increase their reproductive success - the pollen was not only spared, but carried from plant to plant. Insects could still feed, and flowering plants evolved and thrived.
Berries
Berries probably evolved in a similar way, with the plant adapting to cope with animals feeding on its seeds. As a result of this development, the bird or mammal gains a meal, while the plant's seed is not only unharmed, but dispersed, and is often 'activated' by passing through the rigours of a digestive system.
The berries of many plants such as rowan (Sorbus aucuparia), holly (Ilex aquifolium) and bird cherry (Prunus padus), all take part in symbiotic relationships with birds. Some mammals such as the pine marten (Martes martes) also feed on, and disperse, berries.