Organic Evolution in terms of the Implicate and Explicate Orders.

Part XLV

Hymenoptera (wasps, bees, ants) (Sequel)

The evolutionary diversification in the Order Hymenoptera in terms of Strategies (Sequel).

Further REMARKS on the noëtic interpretation of organic evolution.
While studying the evolution of the Order Hymenoptera, seen as chiefly driven by ecological and ethological factors, we gradually perfect our  g e n e r a l  theory of evolution that involves an extra Order of Reality, the Implicate Order. As was explained earlier, to really account for the facts of organic morphogenesis (individual development), and still more so for the facts of evolutionary development -- the existence (and thus also their origin) of sophisticated adaptations and strategies -- has forced us to invoke the existence of an immaterial order -- the Implicate Order -- in addition to the familiar physico-chemical order, the Explicate Order, because the only conceivable evolutionary mechanism that can be at home in the Explicate Order (i.e. that is really physico-chemical), namely the random-genetic-mutation--natural-selection mechanism, turned out not to be the chief factor that drives organic evolution. It can, it is true, generate change, but it cannot be responsible for long-term evolutionary pathways leading to certain definite results and creating new types and subtypes of organisms.
In the Explicate Order (the 'unfolded' Order) everything is temporal, spatial, individual, and local. What we see there are exclusively local physico-chemical interactions. And, when for example, looking at the development of an embryo, we see that the many physico-chemical processes taking place in it are in one or another way  o r g a n i z e d.  But we do  n o t  actually see an organizing agency or force at work. So about the nature and place of the latter much speculations have been put forward. But they remain mere speculations, not discovered facts. So one speaks about "higher-level laws" or "organizing principles" harnessing the fundamental laws of physics. Or one divides our world (i.e. the world that at least possesses a time dimension) into ontological layers determined by different sets of categories (ontological determining principles). All of these speculations serve the purpose of accounting for the alleged fact that  r i g h t  w i t h i n  our observable world there take place the mentioned processes of organization (i.e. processes that direct and guide, and thus organize, other processes), and above all that right into this world the human  m i n d  exists, which is supposed to be immaterial. But also in the case of the human mind and the phenomenon of rational (or irrational) thinking, the only entities we actually encounter upon investigation are local individual space-time processes of a physico-chemical nature. These are organized, it is true, but we cannot concretely point to some definite existing organizational agent directing these processes. If we could, we, without realizing it, would in fact point to entities not belonging to the Explicate Order at all. Therefore, according to me, it makes no sense to look for 'mind', 'organizing principles', 'higher-level laws', 'over-formed categories', etc. in the Explicate Order. If they exist at all, they do not exist there. So if we accept the fact of sophisticated organization (beyond what we see in, say, crystals and other inorganic patterns) we must invoke another Order of Reality in addition to ours to account for these facts. We have done so by presenting the theory of the Implicate Order. It is here that immaterial patterns such as organic strategies are supposed to exist. But what is their relationship with, and relevance to, the patterns in the Explicate Order?. Earlier we had characterized immaterial organic strategies (as being one of the kinds of supposed "organizing principles" or "higher-level laws") as "descriptions", as such expressing the fact that they can be  a b o u t  physical, local, and individual processes (as such processes take place in the Explicate Order), but that they themselves are not at all physical, nor local nor individual. Upon  p r o j e c t i o n  from the Implicate Order into the Explicate Order -- as soon as the conditions in the latter order are such that these patterns can be 'received' onto a substrate
[on this we elaborate further in the REMARK at the beginning of the next document]  -- of such a 'description' (of, say, an organic strategy), it will be  u n f o l d e d  along the space and time dimensions of the Explicate Order and then becoming observable there as, for instance, a definite way of life, combined with a definte morphology and physiology, of representatives of a group of organisms living in some particular ecological environment.
The fact that the immaterial patterns in the Implicate Order are somehow geared to situations in the Explicate Order at all (in contrast to being geared to nothing), and that thus certain patterns might, for example, be organic strategies (in the broadest sense of the term), can be explained by the fact that every immaterial pattern whatsoever is ontologically incomplete. It is only Form, that is, it lacks Prime Matter (the ultimate substrate of form), it lacks temporality, it lacks spatiality, and, finally it lacks individuality. Therefore such a pattern does not really exist in the true sense. Its 'existence' only means its logical consistency (absence of contradiction within it) and its noëtic unity and identity, having it intrinsically distinguished from other such patterns. It IS not, but just IS A PATTERN. Only in this way things 'exist' in the Implicate Order. So it is ontologically natural that such immaterial patterns strife for ontological completion, and they get it by having themselves projected into the Explicate Order. Then they unfold along the Order's space and time dimensions, and become physical, temporal, spatial, individual, etc., i.e. then they receive their ontological completion.

( End of Remarks on noëtics)

Imaginally-parasitic phase

In all up to now discussed phases of evolution the contact of the terebrants took place only with [still] developing, not yet sexually mature, stages of the host. Meanwhile, cases are observed of contact of terebrants also with fully-grown sexually mature hosts. Here we must realize the particular fact that this contact is, not only from the side of the terebrants, but also from the side of their hosts, being realized chiefly only between female individuals. The contact itself is normally of two types [that is, there exist two types of contact between adults, (1) phoresis :  the female terebrant lets itself transport by the adult host to the places where egg-laying of the latter will take place, and where then these eggs are infected, (2) an infection of the adult host itself. Both cases are now expounded in detail.].
In some cases the connection between the adult components [of the contact] expresses itself in the form of so-called phoresis or transport by the female-host of the female-terebrant to the place where egg-laying [by the female-host] will take place, which eggs the transported terebrant then infects.

Such a kind of phoresis may be called "imaginal", to distinguish it from "larval" (transport of planidia, and comparable phenomena). We can further distinguish passive phoresis (as in the cases just mentioned) from active phoresis, which latter is observed almost exclusively in ants, where it is usually placed under the caption of caring for the young or adults. And every sort of transportation of the catch [as is done] by [true] wasps, does, of course, not belong here.

Such cases are mainly observed in serphoid terebrants (Serphoidea) of the family Scelionidae. As the best known example of phoresis serves the behavior of  Rielia  manticida  Kieff.  One usually finds the females of this scelionid under the base of the wings of praying mantids (Mantoptera, Mantodea (or, broader, Dictyoptera), Manteidae) or between the genital lobes of the end of their abdomen. As soon as the female mantid is to lay eggs the  Rielia  leaves its hiding place on the mantid's body, and descends to the foamy mass that forms the ootheca (egg-purse) of the mantid and lays in it its eggs. Also another serphoid terebrant, not closer determined, probably also belonging to the Scelionidae, was found on the body of an adult female of the bug  Anoplocnemis  curvipes  F.  from the family Coreidae (Hemiptera). When the latter began to lay eggs the terebrant laid its eggs on the egg-clutch. Certain authors later observed the presence of females of  Scelio  and  Lepidoscelio  on the body of Orthoptera (grasshoppers, locusts, and the like), especially Acrididae, where they develop in their egg-purses, although other species of these same genera can do it without phoresis.
It is interesting that similar "phoresic" behavior is sometimes observed also among the "shiny terebrants". Thus, one observes females of the chalcid  Anastatus  bifasciatus  Fons. (family Eupelmidae) on the abdomen of the unpaired silk-worm butterfly  Lymantria  dispar  L.,  awaiting the egg-laying by the butterfly. Also the females of another chalcid,  Oligosita  xiphidii  Ferr. (of the family Trichogrammatidae), were found attached on the hind-wings of the bush-cricket  Xiphidion  longipenne  de Haan (Tettigoniidae).  Similar behavior show callimomids of the genus  Podagrion,  which infect, as do the  Rielia's, eggs of mantids.
In all these cases, thanks to such transportation, the female terebrant reaches not only through the right way the place where the host will lay its eggs, but also at the right moment [namely] when the carried-along eggs of the host are not yet covered by firm protective shells. So, exploiting a relatively large and strong host as a means of transport turned out to be a very convenient adaptation of the very small terebrant-egg-eaters.
A second type of contact with adult preys is assumed by a series of relatively large terebrants belonging to different systematic groups. Although these terebrants manage without phoresis, they obtain essentially the same result, namely laying their eggs directly into the body of the host -- usually into the abdomen of the female not yet in a condition to lay eggs. As was already mentioned earlier, the evaniine  Zeuxevania  splendidula  Costa  (Evaniidae) lays its egg into the egg-pack of a cockroach. However, there exists an interesting report according to which that same evaniine (or a biological subspecies of it) has been derived from the adult cockroach  Loboptera  decipiens  Géné,  which was held in a test-tube without ootheca [egg-purse]. This fact evidently indicates that the egg of the terebrant was carried into the female cockroach which was not yet in a position to form an ootheca.
Parallel with this we must also speak about the ichneumonoid terebrants of the subfamily Pimplinae, of which certain representatives (the genera  Polysphincta, Acrodactila) in their larval state live as ectoparasites on freely moving spiders. This, apparently, totally unexpected transition from a development on insects to parasitism on spiders had, as it may be understood, as its origin the predatory life of the larvae of the Pimplinae (such as in  Zaglyptus, Tromatobia), going after egg-cocoons of spiders. A clear hint to this gives the behavior of the terebrant  Zaglyptus  variipes  Crav.,  which, according to NIELSEN, 1935, kills the female spider and then lays its egg into its egg-cocoon. But it turns out that this terebrant, according to data of another investigator (MANEVAL, 1936), is able to develop on the body of the spider itself, and consequently already representing a different biological species -- similar as in the mentioned  Zeuxevania.
From these examples we can see how easily typical egg-eaters, formerly having developed at the expense of egg-clutches of the hosts, could become parasites (more precisely carnivores), now living at the expense of the adult stages of these same hosts. This ease of having transformed one form into the other was determined, of course, by the situation in which the feeding of the terebrant larvae in essence did not change. Here only the behavior of the adults has changed :  the latter now lay their eggs onto the host-females which are not yet in a condition to lay eggs, and [the terebrants laying their eggs] thus not on the already laid egg-clutches of these hosts.
This peculiar way of changing one maternal instinct into another was widely distributed in terebrant evolution. But there is reason to believe that it has played not less an important role also in the [evolutionary] establishment of a series of higher forms [true wasps]. From what has been expounded, also other cases of infection by terebrants of more or less fully-grown stages of various hosts will now be understood. Here, not only the stage of the prey, undergoing the attact of the terebrant, is important, but also the very part of the prey's body and the precise point where the ovipositor of the attacker is sunken into, that is, the organs which are to be destroyed in the prey, and even the place from where the developed terebrant or its larva exits [are important]. In this connection the behavior of the terebrant-braconids (Braconidae) of the subfamily Euphorinae is especially interesting. It is remarkable that the great majority of their species develops in adult beetles of various families :  in leaf-eaters (Chrysomelidae), lady beetles (Coccinellidae), weevils (Curculionidae), mealbeetles (Tenebrionidae), and bark-eaters (Ipidae), and some [of the terebrant-Euphorinae] in grass-bugs of the families Pentatomidae and Miridae. It is observed that certain species or genera have specialized on definite preys of the mentioned families. Best known in this respect are the euphorines of the genus  Perilitus (Dinocampus).
According to data of OGLOBLIN (1913),  Perilitus  terminatus  Nees.  very tenaciously hunts lady beetles, especially the 'seven-spot' (Coccinella  septempunctata  L.)  and the 'variable' (Adonia  variegata  Goez.).  The terebrant hunts down the running-away beetle, holding its ovipositor bent under its [own] body, whereby the apex of the ovipositor almost reaches the terebrant's head. After having identified the right moment, it pushes its ovipositor still more forwardly and drives it into the leathery hinge of the prey's abdomen, in one case from above, in another case from below. The very small terebrant egg having ended up in the beetle's body, swells up to such an extent that it becomes up to a thousand times larger. A mere cursory inspection will not reveal anything indicating the presence of a terebrant larva inside the beetle. The latter continues moving and devouring aphids as a completely normal insect. Only before the very exit of the parasite it becomes less mobile. For the rest, in the case of infection of the smaller species  Adonia  variegeta,  the beetle, containing a larva of  Perilitus  in one of its last developmental stages, can easily be distinguished from healthy beetles :  Its abdomen is strongly stretched, the apices of the elytra are drawn apart from each other, and the wings are relaxed and project from the sides of the body. But, despite such far-reaching changes in the organism, the insect remains mobile and gluttonous as usual. All this points to the fact that the internal organs of crucial importance to the beetle do not suffer in an essential way. Indeed, from the data of OGLOBLIN it becomes clear that the larva of  P.  terminatus  chiefly feeds on the fat-body of the beetle, whereby the latter [the [fat-]body] is so much changed that its condition allows us with certainty to decide whether the beetle is infected or not. About the condition [fate] of the reproductive organs of the prey OGLOBLIN does not make statements. But according to other data the ovaries of infected females were very often damaged. Also in adult female weevils (Curculionidae) (Sitona  sp.), infected with another species of terebrant,  Perilitus  rutilus  Nees.,  the ovaries are atrophied, while in the males the sexual system is still in a functional condition upon the exit of the parasitic larva. Upon exiting the beetle, the larval parasite settles itself longitudinally between the beetle's legs and weaves a cocoon, with its threads partly spinning round the beetle too. A remarkable reaction is observed in the coccinellid  Hippodamia  with respect to this cocoon. When the latter is removed the beetle furiously runs around in search of the cocoon. Having found the latter, it sits down on it and tries again to spin its legs into the loose silk tissue that surrounds the cocoon.
There is an indication that  Perilitus  coccinellae  lays its eggs not only in adult coccinellids but also in their larvae and pupae. Such an assertion is held to be unproven. Nevertheless, it is completely possible, because the different developmental stages of the prey are here usually found together in the same [ecological] conditions. At least in the experiments of CUSHMAN, 1913,  P.  americanus  Riley  attacked many adult coccinellids and their larvae (Megilla  maculata  de Geer, and others). However, in them, only in one adult beetle the development of the terebrant larva was seen. See next Figure.

Figure 1 :  The fully-grown larva of the terebrant  Perilitus  americanus  Riley  exits from the abdomen of a coccinellid [the original subscript reads : leaf-eating] beetle.  (After CUSHMAN, 1913, in MALYSHEV, 1966)

Another representative of the terebrant-Euphorinae,  Microctonus  brevicollis  Hal.,  hibernates in its larval stage in the adult leaf-eating beetles  Haltica  ampelophaga  Gues.  Meanwhile, its summer generation exclusively develops in larvae of the mentioned leaf-eater. And so, one and the same terebrant species, in its alternating generations, turns out to stand as it were in different stages of evolution. But it is interesting that in other species of the same genus  Microctonus  such a complexification in development is not observed. Thus, according to data of  KURDJUMOB and ZNAMENSKY (1917),  Microctonus  sp.,  after having hibernated in the cereal leaf-eaters halticines (Phyllotreta  vittula  Redt.,  Chaetocnema  aridula  Gyll.),  starts to infect these 'fleas' in the spring in their egg-laying period, when the first portion of them are already laid, and the rest being already completely ripe for laying. In such conditions  " the larva of the parasite disturbs the ripening of the later eggs, causing a castration of the beetle and reduces the number of eggs actually laid by it ".  Both summer generations of this terebrant develop again in adult beetles of a new generation, which [beetles] soon after exiting from their cocoons fly off in all directions and then hibernate.
The atrophy of female organs in infected beetles, observed in the just mentioned cases of imaginal parasitism, as well as in other cases, expresses, of course, a chief connection of the development in Euphorinae [with being] at the expense of precisely the sexual production of their preys. This situation definitely points also to the close relationship of these terebrants with the oophagous [egg-eating] phase in their evolutionary past. The presence of such a close relationship is confirmed by the fact of the infection by Euphorins of preys standing far apart with respect to their systematic position -- beetles and bugs [that is, preys, in some cases belonging to the insect Order Coleoptera (beetles), in other cases to the Order Hemiptera (bugs)]. Inadvertently the question comes up where precisely that point lies at which the Euphorinae, searching for the [appropriate] egg-laying place, came in contact with such different preys. Such a point, one must assume, consisted in the egg-clutches of different hosts, laid in similar [ecological] conditions on the surface of plants. Indeed, as we already communicated, the egg-stage of hosts form precisely that point of departure from which the egg-eaters already in the beginning diverged in different directions. And so we come to the conclusion that also the imaginally-parasitic group Euphorinae is genetically connected with the oophagous phase.
Here, we must also mention the ichneumonoid terebrants of the family Aphidiidae -- very minute (2-3 mm) and with a greatly simplified wing-venation. All of them are, as far is known, parasites of aphids, in which their larvae develop as internal solitary parasites. Oviposition by the aphidiids not seldom takes place before the aphid has ripened. See next Figure.

Figure 2 :  The female aphidiid  Lysiphlebus  testaceipes  Cress.  lays an egg in an aphid.
(From BERLAND, 1951, in MALYSHEV, 1966)

Thus, in the case of infection of nymphs of the common grass aphid (Toxoptera  graminum  Rond) by the aphidiid  Lysiphlebus  testaceipes  Cress.  the aphids reach maturity but do not produce offspring. In another case, of the infection of aphids by the terebrant  Aphidius  rapae  Curt.,  the development of the embryos in the body of the aphid (Myzus, Aphis) is delayed during the time of ripening of the egg of the parasite, and later these embryos completely disintegrate. In the same way also the development of the winter eggs is delayed. After first having destroyed germs and eggs in the body of the aphid, the larva of the parasite then consumes all its content. The terebrant concludes its development usually in the emptied body of the aphid. Only the larva of  Praon  exits from the eaten-empty aphid and makes a cocoon under it. The phylogenetic connection with the oophagous phase is also in this case easily established in view of what has been expounded.
It is interesting that, acording to data of  FEDOTOVA and  RJACHOBSKY (1954),  Aphidius  ervi  Hal. -- a parasite of the pea aphid (Acyrthosiphon  pisi  Kalt.)  exits from dead aphids already in the last third of April (in the neighborhood of Kiev), whereby in this time the aphid population, despite its small size (one individual, more rarely 2-3, on one plant), is usually infected by representatives of  Aphidius  for 77-86 percent. There is no doubt that the infection of the aphids by the thermophilous  Aphidius  could not have taken place in such an early period [of the season], but took place already in the last autumn. Indeed, it is found by a number of investigators, in Europe as well as in North America, that the pea aphid in moderate latitudes hibernates in the stage of an egg fertilized in autumn. In the context of this situation the mentioned authors were led to the unexpected and not well-founded by facts assertion that the  "hibernation of the pea aphid in the [climatic] conditions of Kiev is passed through in the larval stage", which also contradicts data established by A. MORDVYLKO (1915) and others. Is it not more probable therefore to hold the other view, namely that what maintains that  Aphidius  ervi  in autumn infects eggs of the aphid and hibernates in them, and [only] in spring develops in aphid females-fundatrices [thus actually develop in imagines anyway]?. This would correspond to our general picture of the origin of Aphidiidae from egg-eaters.
To the imaginal phase of evolution we must, evidently, also reckon those few terebrants which attack preys that are not at all characteristic as being hosts of terebrants, namely ticks and centipedes. Thus, the chacidoid terebrants -- Encyrtidae of the genera  Hunterellus  and  Ixodiphagus -- develop inside ixodioid ticks (Ixodidae), and one serphoid terebrant,  Serphus  ater  Nees.,  was obtained from the centipede  Lithobius  sp.  The transition of certain terebrants to such for them exclusive preys can hardly be understood differently than as [evolutionarily having taken place] through the for them original egg-eaters phase (oophagous phase). This is also supported by the fact that oophagia, and anyway the laying of eggs into the egg-stage of the host, is, at least in the chalcidoid-encyrtids very common. Corresponding data concerning Serphidae are, as a result of still insufficiently being studied, until now [1966] not available.

From all the examples presented, it is clear how widely was followed the above described path of the evolution of maternal instincts of the terebrants. But soon we will meet with the different, the higher forms, which [also] reflect the imaginally-parasitic phase of evolution of the Hymenoptera.
[Anticipating, we present the next Figure] :

Figure 3 :  The female of  Larra  anathema  Rossi.  directs its abdomen under the fore-leg of the mole-cricket  Gryllotalpa  gryllotalpa  L. (Orthoptera), in order to lay an egg under it.
[The genus Larra belongs to a subfamily of the digger-wasps, Sphecidae (Aculeata)]   (After MALYSHEV, 1966)

And thus, as a result of the accomplished analysis of the behavior and way of life of the various terebrants it becomes clear that all above discussed basic lines of evolution of them depart from the original inquilinoid phase -- in some cases directly, in other cases through the oophagous phase, itself having originated from it, or through a phase derived from the oophagous phase. And this is true even of those phases that were last put forward -- the immediately-parasitic and the imaginally-parasitic phases. Such a conclusion totally complies with the thesis presented earlier according to which the terebrants as an independent systematical unit originated from gall-producing Cephoid saw-flies.
[ And, as we will see later on, at least also some (primitive) Aculeata (third Suborder of Hymenoptera, consisting of the true wasps -- higher wasps, the ants, and the bees), such as, for instance the sapigid wasps (Sapygidae), originated also directly from the primitive inquilines. See next Figure] :

Figure 4 :  Sapyga  clavicornis,  Family Sapygidae, Suborder Aculeata.  8 - 10 mm.
(After SEVERA, F., in ZAHRADNIK, J., Thieme's insektengids)

[So all the, in this and the foregoing documents, described evolutionary phases (organic strategies) generally have not evolved one from the other such that it would result in a single evolutionary line, starting from the original inquilines and ending at the imaginally-parasitic phase. On the contrary, there has been several more or less parallel lines starting from the inquilines. And in all this the oophagous strategy plays a pivotal role in the evolution of the Suborder Terebrantia. Noëtically seen (which will later be worked out more fully) we can say that many different terebrant strategies -- now as immaterial patterns in the Implicate Order -- cannot, as it seems, be formally derived from each other, but can be formally derived directly from the original inquilinoid strategy, while many others cannot directly be derived from it, neither from each other, but can be so derived from the oophagous strategy, which itself can be directly derived from the original inquilinoid strategy.
The next diagram symbolizes the noëtic derivability or underivability in a spatial way
] :

Figure 5 :  Diagram spatially illustrating formal derivability and underivability of noëtic patterns (here organic strategies) in the Implicate order.
A, B, C, and D -- noëtic patterns (organic strategies).  Red curve -- noëtic trajectory, expressing actual derivation and non-derivation.
Pattern B can be formally derived from pattern A (and is also actually so derived, as indicated by the noëtic trajectory). Pattern A cannot formally be derived from pattern B.
Pattern D cannot formally be derived from pattern C, but the latter can be derived from the former (but is not actually so derived -- there is no noëtic trajectory going from D to C). The noëtic trajectory passing through pattern C is, at least in the direction of pattern D, a dead-end course.
The uni-directional course of the noëtic trajectory, together with the noëtic derivability and non-derivability, expresses the irreversibility of organic evolution.

Now we have concluded the exposition of the Imaginally-parasitic phase of Hymenopterous evolution, and with it we have concluded the exposition of the evolution of the second suborder of the Hymenoptera, the Terebrantia.
In the next document we will consider the evolution of the third suborder of the Hymenoptera, the Aculeata, consisting of the true wasps, the ants, and the bees. We will begin with the true wasps, mainly consisting of solitary wasps, their origin and their further evolutionary development.

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