African Wildlife & Environment Issue 82

FAUNA, FLORA & WILDLIFE

However, over the years I have slowly become increasingly troubled that many of these ‘stories’ and even some published papers, may or may not be entirely based on solid facts. This is because many are not supported by thorough, peer-reviewed, research (and to say so I must surely have some defendable explanations for such conclusions). Why I have become somewhat sceptical, especially about work on acacias, has its roots back in the 1960s when Jim was doing his fieldwork. First, he taught me about short and long shoots on acacias that have morphologically different leaves, that few if any of the recent papers and tree books ever refer to!Why? Secondly, over the years I have done a few investigations of my own, and just recently I have started to look very closely at A. karroo morphology on the basis of “ Ontology recapitulates phylogeny ”. To clarify these three complex words, a phrase that we learned while undergraduates doing vertebrate palaeontology, is not simple. I checked out my Concise Oxford Dictionary to remind me: • ontology : “ philosophy concerned with the nature of being ” - to me this captures what you see, such as an A. karroo twig (with leaves and spines), part of the tree, encapsulating/summarizing the culmination of a whole developmental/growth pathway of the tree. That is its ontogeny! • recapitulates : “ giving a summary ” – using our twig example: this refers to those developmental/growth pathways that the twig, with all the associated attachments, has gone through to be the modular unit you are looking at. • phylogeny : “ the history of the evolution of a species or group ” – which puts the developmental/ growth pathways of the twig into an evolutionary framework. Before going further, I need readers to understand that there is a basic difference between animals and plants; that Braam vanWyk in his book How to Identify Trees in Southern Africa illustrates so well. Simply put, he reminds us that animals are unitary organisms : meaning that their growth and developmental pathway is fixed. However, plants are MODULAR : meaning that they have no fixed developmental pathway. Therefore, as plants grow and age their form can and does alter from one individual of the same species to another. This is one excellent reason we humans often find plant identification so difficult, while animal identification is mostly simple. Now I also argue that some of the published research on acacias is either based on old pre conceived ideas that are not fully re-interrogated

(very few modern researchers read Bews or even Ross, they merely read what is on the internet and only papers from the last decade or so), or that their work is not refereed by people with what I would call adequate field experience.A good example of the latter is a paper that concluded marulas would not germinate unless they had passed through the gut of an elephant. I know full well that this is not true (as do, many others who have grown marulas). Getting older and caring more about having the freedom to ponder and to question some of the ‘accepted’ research (much to the vexation and disappointment of many peers, colleagues and even ex-students) has allowed me to reconsider why trees are woody and why acacias are spinescent? But please do remember that I trained in the past as a botanist, in a traditional Botany Department, and have been active in the field for 60+ years. I am still passionate about pursuing the truth and sharing that with all people. So let the discussions and debates begin!). Looking at Acacia karroo specifically (and I shall use the old name here as that is my choice) here are some facts which I suggest you check for yourself! Devilish spines on A. karroo in the Little Karoo. Showing them attached to a twig (above) and some of the biggest spines (below) removed from trees. Individually these are up to 130 mm long and inflated

33 | African Wildlife & Environment | Issue 82 (2022)