Nature Notes

As an example, here is a photograph of a Holly Blue butterfly taken in a garden on Belgrave Road. Unsurprisingly, there are holly trees in the garden as well as a certain growth of ivy which helps to support a second brood in the July-September period. 

See here for a videoclip (taken with a phone and therefore not of great quality) - of a pair of holly blues on and about a holly bush.

Holly itself is a plant which has been studied for a peculiarity of its leaves which is known as heterophylly

Indeed, if you observe a naturally growing holly plant carefully, you may observe smooth as well as prickly leaves. Typically, the lower leaves tend to have the expected prickly form but higher up the leaves may turn out to be quite smooth (see image of higher branches of a local holly tree). This phenonemon has long been observed and, it would seem correctly, attributed to the plant's adpatation to protect itself from browsing animals. As the plant grows out of the reach, the leaves no longer produce spines. Recent research has revealed that this does not involve a change in DNA but rather is an everyday example of epigenetics - meaning that the same DNA produces different expressions depending on environmental factors. In an urban environment one may attribute the variation in spinescence to the impact of pruning.

Apart from that of course, one may observe that some holly trees never produce berries, these being the male of the species, on which however the female berry-plants rely for cross-pollination. In addition, of course the male plant produces flower buds which can sustain holly blue larvae in the springtime.

This other photograph shows a single (out-of-season) berry on a branch with some prickly and some smoother leaves at a transition point.

Robins are a common garden bird but you may have noticed that, unlike many other birds and wild animals, they are not shy of humans. On the contrary, you will find that as soon as you start digging in the garden a robin is likely to appear and follow you closely. For more about this habit see here.