Rabbi Tendler is a very highly respected individual in the religious Jewish sphere. He is an Orthodox rabbi and holds a PhD in biology from Columbia. Though I have never actually seen any of his scientific work (I couldn't even find the topic of his dissertation) I think he has some conceptual grasp of biology.
However, he has written an article against the theory of evolution. See it here. Read it before you read my response to it below.
He writes a sensible argument but I think he's talking in a wide arc to avoid talking about things which he wishes to avoid. In the context where he's coming from, I can at least appreciate that he doesn't lambast science itself and even supports the study of it. Now, onto the meat:
He says: "Is there any evidence that such has occurred in nature without the intervention of man? Until a mechanism can be proposed that will enable us to produce such 'races' under scientifically controlled conditions, the evolutionary theory remains but a theory, and one under severe attack from its former proponents."
That's as much an objection as "I've never seen a star form." These things take time. And speciation of long-lived species is difficult in fully controlled conditions. But even so, new strains of bacteria are constantly being made. And there are quite a few fruit-fly species that have been lab-produced.
"The light sensitive eye is advantageous to the organism, but not the colored spot on the arm of a starfish from which it is supposed to have evolved. Why would a starfish with a small red birthmark be selected for survival? "Why were these "sports" or misfits saved for survival? Or by whom?"
At the end of each arm of one class of starfish is a red pigment that serves as a simple eye. Eyes like ours, however, did not evolve from the starfish. We know this because starfish broke off very early and are not in our genealogical line.
Now, supposing the red mark eventually turned into useful eyes (in that order I mean), the red mark would probably be a neutral mutation and would not need special help to survive. Or perhaps they acted to attract predators to attack an arm instead of the center. Since starfish can regenerate lost limbs, it may have been beneficial to have these sightless spots which actually protected the main body of the ancient starfish. But here we're really talking about ancient events. The farther back you go the harder it is to piece together what happened. If Rabbi Tendler had asked about a phylum much more well known and studied, folks like me would probably have better answers. Why would he choose such a random out of the blue example to focus on?
"'Vestigial organs' most often reflect our ignorance rather than our investigative skills. The Thymus gland, now known to be a major component of our immune system, was listed as a vestigial organ. The appendix, the classic vestigial organ is now suspected of playing a role in immune mechanisms as well."
People do make mistakes and the thymus gland error was corrected, I think, around the turn of the last century. But the point about the appendix is, not whether it truly has zero purpose, it may have been co-opted for some minor role. But in species with large plant diets, the appendix is huge. For non-herbivores, the appendix is much smaller, if not absent. People can live quite well without an appendix. I think the connection is obvious that the appendix is derived from an older organ. It has no necessary purpose in the body. As a design, it's really not up there.
"Gradualism, the basic tenet of evolutionary theory was rejected on the basis of its former greatest proof- the fossil record....The principle feature of individual species within the fossil record is stasis, not change. The record, read without bias, reveals that species remained unchanged and then suddenly disappeared to be replaced by substantially different but related species. There are no transitional forms! All have been postulated to complete the record but they do not exist except in the imagination of the evolutionists."
This is a common creationist canard. In fact, gradualism is still in force but it is seen that it does not predict what it should for all species. It does still work for a good number. The evolution of the horse is well preserved in the fossil record and it is the classic example of gradualism. And as for the "no transitional forms" claim, I only need to point to the archeopteryx as the famous example. There are many others, too. Just look them up and see for yourselves.
Then he goes into a bit about arguments among scientists about how evolution happened as if to show that since there is no unanimity it all must be wrong. But I think the fallaciousness of that method is clear.
And later on he says "Neither the age of the earth, the fossil finds of strange creatures nor the evolution of man, posed any "threat" to Torah truth as understood by the Tifereth Yisroel."
This means that even if evolution happens to be true it still is not a problem to the factuality of the Torah and Judaism. He's trying to play to both sides, but that's clearly a contradiction. You can't both be trying to show how evolution is wrong and showing how evolution doesn't pose a problem to Judaism even if it is right. Why would he bother showing how bankrupt evolution is if it actually poses no problem?
"To sum up: In 1987 there is not one piece of scientific evidence for macroevolution or the development of one species from another. All our work in genetics, molecular biology, recombinant DNA explains variations within the species but does not offer any mechanism for the development of new species."
Well, that's simply not true. There are a number of proposed mechanisms and each has evidence to support them. Also, these mechanisms are not mutually exclusive and may all be correct. Look up allopatric speciation. It is speciation from being separated for some period of time and the two or more groups going through natural selection and finding themselves incompatible when the species reconverge. See actual examples of "ring species" where this is occurring as this is being written.
Sympatric speciation is where the species is split because of separated resources. Take the example of Rhagoletis (fruit flies) which need to lay their eggs on fruit as they become ripe. In America, R. pomonella would lay eggs on Hawthorns. Yet, when apple trees were introduced in the 1860s some began laying eggs on them. But the two fruits ripen at different times. So those that laid their eggs on one lost genetic contact with those which laid on the other. Two groups were formed. These do not interbreed much. Interbreeding is about 5%. But even in this short a time, 150 years, the two groups are genetically distinguishable. Races have been formed.
Transformative speciation is an example where a species is simply very long lived. Like horses, for example, a line might not necessarily split into more species, but just slowly form into a new one.
Among plants, speciation is more common because they are not as vulnerable to negative mutations. Hybrids often form but instead of being sterile, like a mule, they will simply double their chromosomes in a function known as autopolyploidy or alloployploidy and each set will act as their haploid sets for reproduction. And even those that are sterile, they often persist anyway because they can simply grow asexually. A good example is Spartina alterniflora, a tough seaside grass. Hybridized with S. maritina, together they formed a sterile grass S. townsendii which doubled its chromosomes and formed S. anglion which is fertile.
Now, I understand where Rabbi Tendler is coming from. He writes a well written paper. And it would probably be very convincing to any regular Modern Orthodox Jew. I just disagree with him, as do most scientists. As do the facts.